Add Firestore transaction example (#442)

diff --git a/packages/cloud_firestore/CHANGELOG.md b/packages/cloud_firestore/CHANGELOG.md
index 65f1513..46f73a3 100644
--- a/packages/cloud_firestore/CHANGELOG.md
+++ b/packages/cloud_firestore/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.7.0+1
+
+* Add transactions example to README.
+
 ## 0.7.0
 
 * **Breaking change**. `snapshots` is now a method instead of a getter.

diff --git a/packages/cloud_firestore/README.md b/packages/cloud_firestore/README.md
index 7085989..eeae48b 100755
--- a/packages/cloud_firestore/README.md
+++ b/packages/cloud_firestore/README.md

@@ -62,6 +62,18 @@
 }
 ```
 
+Running a transaction:
+
+```dart
+final DocumentReference postRef = Firestore.instance.document('posts/123');
+Firestore.instance.runTransaction((Transaction tx) async {
+  DocumentSnapshot postSnapshot = await tx.get(postRef);
+  if (postSnapshot.exists) {
+    tx.update(postRef, <String, dynamic>{'likesCount': postSnapshot.data['likesCount'] + 1});
+  }
+});
+```
+
 ## Getting Started
 
 See the `example` directory for a complete sample app using Cloud Firestore.

diff --git a/packages/cloud_firestore/pubspec.yaml b/packages/cloud_firestore/pubspec.yaml
index 4dc4152..14d53f7 100755
--- a/packages/cloud_firestore/pubspec.yaml
+++ b/packages/cloud_firestore/pubspec.yaml

@@ -3,7 +3,7 @@
   live synchronization and offline support on Android and iOS.
 author: Flutter Team <flutter-dev@googlegroups.com>
 homepage: https://github.com/flutter/plugins/tree/master/packages/cloud_firestore
-version: 0.7.0
+version: 0.7.0+1
 
 flutter:
   plugin: