[bazel] Add fixes for --incompatible_load_{cc,java,proto}_rules_from_bzl (Part 2)

This change adds the required loads to examples and zlib.
For full compatibility with --incompatible_load_{cc,java,proto}_rules_from_bzl,
we will need to roll gtest to a newer version.
diff --git a/WORKSPACE b/WORKSPACE
index ee505d1..5e6214b 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -1,5 +1,10 @@
 workspace(name = "com_google_protobuf")
 
+local_repository(
+    name = "com_google_protobuf_examples",
+    path = "examples",
+)
+
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 load("//:protobuf_deps.bzl", "protobuf_deps")
 
@@ -19,13 +24,6 @@
     urls = ["https://pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz#md5=34eed507548117b2ab523ab14b2f8b55"],
 )
 
-http_archive(
-    name = "bazel_skylib",
-    sha256 = "bbccf674aa441c266df9894182d80de104cabd19be98be002f6d478aaa31574d",
-    strip_prefix = "bazel-skylib-2169ae1c374aab4a09aa90e65efe1a3aad4e279b",
-    urls = ["https://github.com/bazelbuild/bazel-skylib/archive/2169ae1c374aab4a09aa90e65efe1a3aad4e279b.tar.gz"],
-)
-
 bind(
     name = "python_headers",
     actual = "//util/python:python_headers",