chore(test): remove TestBed

Instead, use TestComponentBuilder.

Closes #2354

modules/angular2/test.ts

@@ -7,5 +7,5 @@
  * This module is not included in the `angular2` module; you must import the test module explicitly.
  *
  */
-export * from './src/test_lib/test_bed';
+export * from './src/test_lib/test_component_builder';
 export * from './src/test_lib/test_injector';