allow angular.d.ts to be imported using AMD

currently if you do 
import angular = require("angular"); 
tsc will throw 2071 - Unable to resolve external module 'angular'
this 
declare module 'angular'{
    export var angular:ng.IAngularStatic;
}
declares such a module.

angularjs/angular.d.ts

@@ -6,6 +6,11 @@
 
 /// <reference path="../jquery/jquery.d.ts" />
 
+declare module 'angular'{
+    export var angular:ng.IAngularStatic;
+}
+
+
 declare var angular: ng.IAngularStatic;
 
 // Support for painless dependency injection