chore(lint): Added license headers to most TypeScript files

Relates to #9380

modules/@angular/examples/facade/ts/async/observable.ts

@@ -1,3 +1,11 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
 // #docregion Observable
 import {Observable, Subscriber} from 'rxjs/Rx';
 var obs = new Observable<number>((obs: Subscriber<number>) => {