Restructure pkg/unittest and pkg/webdriver to follow the pub conventions.

pkg/unittest/lib/unittest.dart

Index: pkg/unittest/lib/unittest.dart
===================================================================
--- pkg/unittest/lib/unittest.dart	(revision 0)
+++ pkg/unittest/lib/unittest.dart	(working copy)
@@ -148,20 +148,10 @@
 library unittest;
 
 import 'dart:isolate';
+import 'matcher.dart';
+export 'matcher.dart';
 
-part 'collection_matchers.dart';
 part 'config.dart';
-part 'core_matchers.dart';
-part 'description.dart';
-part 'expect.dart';
-part 'future_matchers.dart';
-part 'interfaces.dart';
-part 'map_matchers.dart';
-part 'matcher.dart';
-part 'mock.dart';
-part 'numeric_matchers.dart';
-part 'operator_matchers.dart';
-part 'string_matchers.dart';
 part 'test_case.dart';
 
 /** [Configuration] used by the unittest library. */
@@ -854,6 +844,8 @@
     return;
   }
   _initialized = true;
+  // Hook our async guard into the matcher library.
+  wrapAsync = expectAsync1;
 
   _tests = <TestCase>[];
   _testRunner = _nextBatch;