title: register device token manually with Firebase Notifications
body: <p>I would like to integrate my existing ionic ios app with the new <a href="https://firebase.google.com/docs/notifications/" rel="nofollow">firebase notification</a> service. But i could not find any documentation about registering a device token manually with the rest api or web api. </p>
  
  <p>Am i missing any new feature? Or is this not possible with the current libraries?</p>