feat(router): adds the router to the self-executing bundle.

Due to limitation of system build, the router cannot have its own sfx
bundle.

Fixes an issue with RouteConfig decorator by moving it into its own
file.

modules/angular2/angular2_sfx.es6

@@ -1,10 +1,16 @@
 import * as angular from './angular2';
+// the router should have its own SFX bundle 
+// But currently the module arithemtic 'angular2/router_sfx - angular2/angular2',
+// is not support by system builder.
+import * as router from './router';
+
+angular.router = router;
 
 var _prevAngular = window.angular;
 
 /**
  * Calling noConflict will restore window.angular to its pre-angular loading state
- * and return the angular module object. 
+ * and return the angular module object.
  */
 angular.noConflict = function() {
   window.angular = _prevAngular;