feat(typings): allow defining custom namespace for bundle

Allows declaring a bundle's namespace in generated typings file,
which should correspond to the global object representing the module
inside its bundle.

BREAKING CHANGE
    The router was previously exported as ng.router in the 
    angular.sfx.dev.js bundle, but now it is exported as ngRouter.

Closes #2948

Closes #3544

modules/angular2/router.ts

@@ -21,6 +21,7 @@ export {OnActivate, OnDeactivate, OnReuse, CanDeactivate, CanReuse} from './src/
 export {CanActivate} from './src/router/lifecycle_annotations';
 export {Instruction, ComponentInstruction} from './src/router/instruction';
 export {Url} from './src/router/url_parser';
+export {OpaqueToken, Type} from 'angular2/angular2';
 
 import {LocationStrategy} from './src/router/location_strategy';
 import {HTML5LocationStrategy} from './src/router/html5_location_strategy';