Increase /events timeout to 30 secs. We don't need it so low anymore to get around request suppression when changing rooms, since there is just a single event stream now.

Remove old polling stuff from RoomController. Added service comments. Do not start the event stream on startup unless you have credentials.

Event streaming now happens on an app level, rather than a per-room level. Make eventStreamService manage it's own repolling provided no one calls stop() on it. Couple the stream with eventHandlerService so any controller can just blithely call eventStreamService.resume() and expect to 'get stuff' without having to handle promises (though resume() still returns a promise for that request and proxies it through $q). Kill and reset the stream if you logout.

Added event handler service which.. handles events. More specifically, it $broadcasts events depending on their type, and does processing on events (shuffling keys, adding events to $rootScope so displays will automatically update, sending delivery receipts, and so on). Some of this logic was previously contained in the RoomController, which fails the moment you add >1 room into the mix, hence requiring a Service to handle events, rather than having each individual controller maintain their part of the world.

Added event stream service which neatly blobs together requests / state for the event stream. This depends on matrix service to do the actual hit. Currently this has exactly the same behaviour as before.