refactor: change provide(...) for {provide: ...}

- provide() is deprecated,
- {} syntax is required by the offline compiler

modules/playground/src/routing/index.ts

@@ -1,10 +1,9 @@
 import {InboxApp} from './app/inbox-app';
-import {provide} from '@angular/core';
 import {bootstrap} from '@angular/platform-browser';
 import {HashLocationStrategy, LocationStrategy} from '@angular/common';
 import {ROUTER_PROVIDERS} from '@angular/router-deprecated';
 
 export function main() {
   bootstrap(InboxApp,
-            [ROUTER_PROVIDERS, provide(LocationStrategy, {useClass: HashLocationStrategy})]);
+            [ROUTER_PROVIDERS, {provide: LocationStrategy, useClass: HashLocationStrategy}]);
 }