title: Dynamically Change Page <Head> In Angular2
body: <p>In AngularJS 1 we simply add ng-app at top of the HTML tag and bind services to change metadata on the fly.</p>
  
  <p>But in Angular2 the quickstart app in official site made index.html completely static (css, meta, ...), only left app tag to bind with bootstrap()</p>
  
  <p>Now how we can do when we want to build many panel with different style and js plugins, meta keyword... </p>