feat(core): renam AMBIENT_DIRECTIVES and AMBIENT_PIPES into PLATFORM_DIRECTIVES and PLATFORM_PIPES

After discussing it we decided that PLATFORM_ is a better prefix for directives available everywhere in the app.

BREAKING CHANGE

AMBIENT_DIRECTIVES -> PLATFORM_DIRECTIVES
AMBIENT_PIPES -> PLATFORM_PIPES

Closes #5201

modules/angular2/test/compiler/runtime_metadata_spec.ts

@@ -37,7 +37,7 @@ import {
 import {TEST_PROVIDERS} from './test_bindings';
 import {MODULE_SUFFIX} from 'angular2/src/compiler/util';
 import {IS_DART} from 'angular2/src/facade/lang';
-import {AMBIENT_DIRECTIVES} from 'angular2/src/core/ambient';
+import {PLATFORM_DIRECTIVES} from 'angular2/src/core/platform_directives_and_pipes';
 
 export function main() {
   describe('RuntimeMetadataResolver', () => {
@@ -85,10 +85,10 @@ export function main() {
                .toEqual([resolver.getMetadata(DirectiveWithoutModuleId)]);
          }));
 
-      describe("ambient directives", () => {
-        beforeEachProviders(() => [provide(AMBIENT_DIRECTIVES, {useValue: [ADirective]})]);
+      describe("platform directives", () => {
+        beforeEachProviders(() => [provide(PLATFORM_DIRECTIVES, {useValue: [ADirective]})]);
 
-        it('should include ambient directives when available',
+        it('should include platform directives when available',
            inject([RuntimeMetadataResolver], (resolver: RuntimeMetadataResolver) => {
              expect(resolver.getViewDirectivesMetadata(ComponentWithEverything))
                  .toEqual([

modules/angular2/test/public_api_spec.ts

@@ -147,7 +147,7 @@ var NG_ALL = [
   'By',
   'CORE_DIRECTIVES',
   'COMMON_DIRECTIVES',
-  'AMBIENT_DIRECTIVES:js',
+  'PLATFORM_DIRECTIVES:js',
   'ChangeDetectionError',
   'ChangeDetectionError.context',
   'ChangeDetectionError.location',
@@ -399,7 +399,7 @@ var NG_ALL = [
   'CyclicDependencyError.message=',
   'CyclicDependencyError.stackTrace',
   'COMMON_PIPES',
-  'AMBIENT_PIPES:js',
+  'PLATFORM_PIPES:js',
   'DOCUMENT',
   'DatePipe',
   'DatePipe.supports()',