fix(typings): test our .d.ts with --noImplicitAny

This matches how DefinitelyTyped tests it, so we are
one step closer to publishing the same file we generate.

See #3195

modules/angular2/src/core/application_tokens.ts

@@ -22,4 +22,4 @@ export const appComponentRefPromiseToken = CONST_EXPR(new OpaqueToken('Promise<C
  *
  * ```
  */
-export const appComponentTypeToken = CONST_EXPR(new OpaqueToken('RootComponent'));
+export const appComponentTypeToken: OpaqueToken = CONST_EXPR(new OpaqueToken('RootComponent'));