Implemented webrtc functionality into diaspora v0.001

Usage:

* open dialog window and choose whether you'd like to join or create a room
  -> on create: you create a access token and wait for connections
  -> on join: you need a access token from your friend to join the room.
              copy and paste it into the text field and click `join`
* a new chat window will be displayed at the bottom of your window
  and you'll be able to interacte with the other clients

Upcoming:

* clean code
* add video and audio functionality