refactor: export core APIs from angular2/core

This change moves many APIs to the angular2/core export.

This change also automatically adds FORM_BINDINGS in
the application root injector.

BREAKING CHANGE:
    Many dependencies that were previously exported from specific
    APIs are now exported from angular2/core. Affected exports, which
    should now be included from angular2/core include:

    angular2/forms
    angular2/di
    angular2/directives
    angular2/change_detection
    angular2/bootstrap (except for dart users)
    angular2/render
    angular2/metadata
    angular2/debug
    angular2/pipes
Closes #3977

modules/angular2/test/compiler/change_definition_factory_spec.ts

@@ -9,21 +9,14 @@ import {
   inject,
   it,
   xit,
-  TestComponentBuilder,
-  asNativeElements,
-  By
+  TestComponentBuilder
 } from 'angular2/test_lib';
-
 import {MapWrapper} from 'angular2/src/core/facade/collection';
 import {isBlank} from 'angular2/src/core/facade/lang';
-
 import {HtmlParser} from 'angular2/src/compiler/html_parser';
 import {DirectiveMetadata, TypeMetadata, ChangeDetectionMetadata} from 'angular2/src/compiler/api';
-
 import {MockSchemaRegistry} from './template_parser_spec';
-
 import {TemplateParser} from 'angular2/src/compiler/template_parser';
-
 import {
   Parser,
   Lexer,
@@ -38,10 +31,7 @@ import {
   BindingTarget,
   ChangeDetector
 } from 'angular2/src/core/change_detection/change_detection';
-
 import {Pipes} from 'angular2/src/core/change_detection/pipes';
-
-
 import {createChangeDetectorDefinitions} from 'angular2/src/compiler/change_definition_factory';
 
 export function main() {

modules/angular2/test/compiler/template_loader_spec.ts

@@ -9,9 +9,7 @@ import {
   inject,
   it,
   xit,
-  TestComponentBuilder,
-  asNativeElements,
-  By
+  TestComponentBuilder
 } from 'angular2/test_lib';
 
 import {HtmlParser} from 'angular2/src/compiler/html_parser';