refactor: rename annotations to metadata

BREAKING CHANGE (maybe)

Well as long as our customers use public API this should not be a
breaking change, but we have changed import structure as well as
internal names, so it could be breaking.

import:
  angular2/annotations => angular2/metadata

Classes:
  *Annotations => *Metadata
  renderer.DirectiveMetadata => renderer.RendererDirectiveMetadata
  renderer.ElementBinder => renderer.RendererElementBinder
  impl.Directive => impl.DirectiveMetadata
  impl.Component => impl.ComponentMetadata
  impl.View => impl.ViewMetadata

Closes #3660

modules/angular2/test/transform/directive_linker/simple_export_files/bar.ng_deps.dart

@@ -3,7 +3,7 @@ library bar.ng_deps.dart;
 import 'bar.dart';
 export 'bar.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 export 'foo.dart';
 
 var _visited = false;

modules/angular2/test/transform/directive_linker/simple_export_files/expected/bar.ng_deps.dart

@@ -3,7 +3,7 @@ library bar.ng_deps.dart;
 import 'bar.dart';
 export 'bar.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 export 'foo.dart';
 import 'foo.ng_deps.dart' as i0;
 

modules/angular2/test/transform/directive_linker/simple_export_files/expected/foo.ng_deps.dart

@@ -3,7 +3,7 @@ library foo.ng_deps.dart;
 import 'foo.dart';
 export 'foo.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 
 var _visited = false;
 void initReflector() {

modules/angular2/test/transform/directive_linker/simple_export_files/foo.ng_deps.dart

@@ -3,7 +3,7 @@ library foo.ng_deps.dart;
 import 'foo.dart';
 export 'foo.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 
 var _visited = false;
 void initReflector() {

modules/angular2/test/transform/directive_linker/simple_files/bar.ng_deps.dart

@@ -3,7 +3,7 @@ library bar.ng_deps.dart;
 import 'bar.dart';
 export 'bar.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 import 'foo.dart' as dep;
 
 var _visited = false;

modules/angular2/test/transform/directive_linker/simple_files/expected/bar.ng_deps.dart

@@ -3,7 +3,7 @@ library bar.ng_deps.dart;
 import 'bar.dart';
 export 'bar.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 import 'foo.dart' as dep;
 import 'foo.ng_deps.dart' as i0;
 

modules/angular2/test/transform/directive_linker/simple_files/expected/foo.ng_deps.dart

@@ -3,7 +3,7 @@ library foo.ng_deps.dart;
 import 'foo.dart';
 export 'foo.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 
 var _visited = false;
 void initReflector() {

modules/angular2/test/transform/directive_linker/simple_files/foo.ng_deps.dart

@@ -3,7 +3,7 @@ library foo.ng_deps.dart;
 import 'foo.dart';
 export 'foo.dart';
 import 'package:angular2/src/reflection/reflection.dart' as _ngRef;
-import 'package:angular2/src/core/annotations_impl/annotations.dart';
+import 'package:angular2/src/core/metadata.dart';
 
 var _visited = false;
 void initReflector() {