Rework app.data.user so that it is always available, and the LoginView can trigger from its changes
Remove login/logout callbacks from services.js now they aren't necessary
Fix incorrect parameter usage by createPresenceSocket
Initial support for sending and receiving login functions via the worker
Remove websocket from services.js now that it is in the worker
Remove old websocket listener from UsersView as this has been replaced by listening to the UserSet model.
Add empty services_test.js file ready for tests
Fix the front-end tests as the data structure wasn't matching what the port actually sends
Implement websocket closing in the worker, and handle unexpected websocket disconnections in the UI.
Change default presence to be disconnected, move the detection of presence unavailable error cases to the UI.
Add an isLoggedIn function to the user model
Remove unnecessary commented out line
Merge pull request #78 from Standard8/signin

Hook up signing in to the worker and complete hooking up of the users presence list to the view