Setting up for a v0.3.0 release (#134)

diff --git a/packages/flutter_markdown/CHANGELOG.md b/packages/flutter_markdown/CHANGELOG.md
index 195659e..7cda4a9 100644
--- a/packages/flutter_markdown/CHANGELOG.md
+++ b/packages/flutter_markdown/CHANGELOG.md
@@ -1,3 +1,9 @@
+## 0.3.0
+
+ * Supporting GitHub flavoured Markdown
+ * Supporting strikethrough
+ * Convert TextSpan to use new InlineSpan API
+
 ## 0.2.0
 
 * Updated environment sdk constraints to make the package
diff --git a/packages/flutter_markdown/example/lib/main.dart b/packages/flutter_markdown/example/lib/main.dart
index 1c7a2aa..988bf10 100644
--- a/packages/flutter_markdown/example/lib/main.dart
+++ b/packages/flutter_markdown/example/lib/main.dart
@@ -5,7 +5,8 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_markdown/flutter_markdown.dart';
 
-const String _markdownData = """# Markdown Example
+const String _markdownData = """
+# Markdown Example
 Markdown allows you to easily include formatted text, images, and even formatted Dart code in your app.
 
 ## Titles
@@ -95,14 +96,18 @@
 """;
 
 void main() {
-  runApp(MaterialApp(
-    title: "Markdown Demo",
-    home: Scaffold(
-      appBar: AppBar(title: const Text('Markdown Demo')),
-      body: Markdown(
-        data: _markdownData,
-        imageDirectory: 'https://raw.githubusercontent.com',
+  runApp(
+    MaterialApp(
+      title: "Markdown Demo",
+      home: Scaffold(
+        appBar: AppBar(title: const Text('Markdown Demo')),
+        body: SafeArea(
+          child: Markdown(
+            data: _markdownData,
+            imageDirectory: 'https://raw.githubusercontent.com',
+          ),
+        ),
       ),
     ),
-  ));
+  );
 }
diff --git a/packages/flutter_markdown/example/pubspec.lock b/packages/flutter_markdown/example/pubspec.lock
index 997e2b3..3ece2e2 100644
--- a/packages/flutter_markdown/example/pubspec.lock
+++ b/packages/flutter_markdown/example/pubspec.lock
@@ -5,56 +5,56 @@
     dependency: transitive
     description:
       name: archive
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.10"
   args:
     dependency: transitive
     description:
       name: args
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.5.2"
   async:
     dependency: transitive
     description:
       name: async
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.3.0"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.5"
   charcode:
     dependency: transitive
     description:
       name: charcode
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.2"
   collection:
     dependency: transitive
     description:
       name: collection
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.14.11"
   convert:
     dependency: transitive
     description:
       name: convert
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.1"
   crypto:
     dependency: transitive
     description:
       name: crypto
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.3"
   flutter:
@@ -68,7 +68,7 @@
       path: ".."
       relative: true
     source: path
-    version: "0.2.0"
+    version: "0.3.0"
   flutter_test:
     dependency: "direct dev"
     description: flutter
@@ -78,56 +78,56 @@
     dependency: transitive
     description:
       name: image
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.4"
   markdown:
     dependency: transitive
     description:
       name: markdown
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.1"
   matcher:
     dependency: transitive
     description:
       name: matcher
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.5"
   meta:
     dependency: transitive
     description:
       name: meta
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.7"
   path:
     dependency: transitive
     description:
       name: path
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.6.4"
   pedantic:
     dependency: transitive
     description:
       name: pedantic
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.8.0+1"
   petitparser:
     dependency: transitive
     description:
       name: petitparser
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.4.0"
   quiver:
     dependency: transitive
     description:
       name: quiver
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.5"
   sky_engine:
@@ -139,64 +139,64 @@
     dependency: transitive
     description:
       name: source_span
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.5.5"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.9.3"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.0"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.5"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.0"
   test_api:
     dependency: transitive
     description:
       name: test_api
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.5"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.6"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.8"
   xml:
     dependency: transitive
     description:
       name: xml
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "3.5.0"
 sdks:
-  dart: ">=2.4.0 <3.0.0"
+  dart: ">=2.5.0 <3.0.0"
diff --git a/packages/flutter_markdown/example/pubspec.yaml b/packages/flutter_markdown/example/pubspec.yaml
index 851f12f..211b43d 100644
--- a/packages/flutter_markdown/example/pubspec.yaml
+++ b/packages/flutter_markdown/example/pubspec.yaml
@@ -3,7 +3,7 @@
 publish_to: 'none'
 
 environment:
-  sdk: ">=2.1.0 <3.0.0"
+  sdk: ">=2.5.0 <3.0.0"
 
 dependencies:
   flutter:
diff --git a/packages/flutter_markdown/pubspec.lock b/packages/flutter_markdown/pubspec.lock
index 7758c46..9b824c4 100644
--- a/packages/flutter_markdown/pubspec.lock
+++ b/packages/flutter_markdown/pubspec.lock
@@ -5,70 +5,63 @@
     dependency: transitive
     description:
       name: analyzer
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.36.4"
-  archive:
-    dependency: transitive
-    description:
-      name: archive
-      url: "https://pub.flutter-io.cn"
-    source: hosted
-    version: "2.0.10"
   args:
     dependency: transitive
     description:
       name: args
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.5.2"
   async:
     dependency: transitive
     description:
       name: async
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.3.0"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.5"
   charcode:
     dependency: transitive
     description:
       name: charcode
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.2"
   collection:
     dependency: transitive
     description:
       name: collection
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.14.11"
   convert:
     dependency: transitive
     description:
       name: convert
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.1"
   crypto:
     dependency: transitive
     description:
       name: crypto
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.3"
   csslib:
     dependency: transitive
     description:
       name: csslib
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.16.1"
   flutter:
@@ -85,210 +78,210 @@
     dependency: transitive
     description:
       name: front_end
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.1.19"
   glob:
     dependency: transitive
     description:
       name: glob
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.7"
+    version: "1.2.0"
   html:
     dependency: transitive
     description:
       name: html
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.14.0+3"
   http:
     dependency: transitive
     description:
       name: http
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.0+2"
   http_multi_server:
     dependency: transitive
     description:
       name: http_multi_server
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.0"
   http_parser:
     dependency: transitive
     description:
       name: http_parser
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "3.1.3"
-  image:
-    dependency: transitive
-    description:
-      name: image
-      url: "https://pub.flutter-io.cn"
-    source: hosted
-    version: "2.1.4"
   io:
     dependency: transitive
     description:
       name: io
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.3.3"
   js:
     dependency: transitive
     description:
       name: js
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.6.1+1"
   json_rpc_2:
     dependency: transitive
     description:
       name: json_rpc_2
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.0"
   kernel:
     dependency: transitive
     description:
       name: kernel
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.3.19"
   markdown:
     dependency: "direct main"
     description:
       name: markdown
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.1"
   matcher:
     dependency: transitive
     description:
       name: matcher
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.5"
   meta:
     dependency: transitive
     description:
       name: meta
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.7"
   mime:
     dependency: transitive
     description:
       name: mime
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.9.6+3"
   mockito:
     dependency: "direct dev"
     description:
       name: mockito
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "3.0.2"
   multi_server_socket:
     dependency: transitive
     description:
       name: multi_server_socket
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.2"
+  node_interop:
+    dependency: transitive
+    description:
+      name: node_interop
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.3"
+  node_io:
+    dependency: transitive
+    description:
+      name: node_io
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.1+2"
   node_preamble:
     dependency: transitive
     description:
       name: node_preamble
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.4.8"
   package_config:
     dependency: transitive
     description:
       name: package_config
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.0"
   package_resolver:
     dependency: transitive
     description:
       name: package_resolver
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.10"
   path:
     dependency: transitive
     description:
       name: path
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.6.4"
   pedantic:
     dependency: transitive
     description:
       name: pedantic
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.8.0+1"
-  petitparser:
-    dependency: transitive
-    description:
-      name: petitparser
-      url: "https://pub.flutter-io.cn"
-    source: hosted
-    version: "2.4.0"
   pool:
     dependency: transitive
     description:
       name: pool
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.4.0"
   pub_semver:
     dependency: transitive
     description:
       name: pub_semver
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.4.2"
   quiver:
     dependency: transitive
     description:
       name: quiver
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.5"
   shelf:
     dependency: transitive
     description:
       name: shelf
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.7.5"
   shelf_packages_handler:
     dependency: transitive
     description:
       name: shelf_packages_handler
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.4"
   shelf_static:
     dependency: transitive
     description:
       name: shelf_static
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.8"
   shelf_web_socket:
     dependency: transitive
     description:
       name: shelf_web_socket
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.3"
   sky_engine:
@@ -300,120 +293,113 @@
     dependency: transitive
     description:
       name: source_map_stack_trace
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.5"
   source_maps:
     dependency: transitive
     description:
       name: source_maps
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.10.8"
   source_span:
     dependency: transitive
     description:
       name: source_span
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.5.5"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.9.3"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.0"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.5"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.0"
   test:
     dependency: transitive
     description:
       name: test
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.6.3"
   test_api:
     dependency: transitive
     description:
       name: test_api
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.5"
   test_core:
     dependency: transitive
     description:
       name: test_core
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.5"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.6"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.8"
   vm_service_client:
     dependency: transitive
     description:
       name: vm_service_client
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.6+3"
   watcher:
     dependency: transitive
     description:
       name: watcher
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "0.9.7+12"
   web_socket_channel:
     dependency: transitive
     description:
       name: web_socket_channel
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.0"
-  xml:
-    dependency: transitive
-    description:
-      name: xml
-      url: "https://pub.flutter-io.cn"
-    source: hosted
-    version: "3.5.0"
   yaml:
     dependency: transitive
     description:
       name: yaml
-      url: "https://pub.flutter-io.cn"
+      url: "https://pub.dartlang.org"
     source: hosted
     version: "2.2.0"
 sdks:
-  dart: ">=2.4.0 <3.0.0"
+  dart: ">=2.5.0 <3.0.0"
diff --git a/packages/flutter_markdown/pubspec.yaml b/packages/flutter_markdown/pubspec.yaml
index 4f1e7fb..f16d711 100644
--- a/packages/flutter_markdown/pubspec.yaml
+++ b/packages/flutter_markdown/pubspec.yaml
@@ -2,7 +2,7 @@
 author: Flutter Authors <flutter-dev@googlegroups.com>
 description: A Markdown renderer for Flutter.
 homepage: https://github.com/flutter/flutter_markdown
-version: 0.2.0
+version: 0.3.0
 
 dependencies:
   flutter:
@@ -15,7 +15,7 @@
   mockito: ^3.0.0
 
 environment:
-  sdk: '>=2.0.0-dev.58.0 <3.0.0'
+  sdk: '>=2.5.0 <3.0.0'
 
 flutter:
   assets: