title: in firebase how to remove all observers, rather than observers for a specific ref
body: <p>I'm creating a firebase app with a signOut.  My question is does </p>
  
  <pre><code>   class func signOut(callback:((error:NSError?)-&gt;Void)) {
          let ref = Firebase(url:firebaseHost)
          ref.unauth()
          ref.removeAllObservers()
          let err = UserCredentials.delete()
          callback(error:err)
      }
  </code></pre>
  
  <p>remove just observers for the root reference?  I'd like to remove all observers that were set in other parts of the app for several different queries.</p>
  
  <p>Do I have to let ref... and re-create all those references to then remove observers?</p>
  
  <p>Does unauth disconnect and remove observers?  Is there jusa simple disconnect method for the client?</p>