Site-wide WebSocket implementation

[jeda]

This would help to have state correctly synced (whenver users are in rooms or not), properly update profiles in case of a refresh across all clients.

Taken a bit from crybapp/web#6.

[Soliel]

Personally, I think API should actually be split into a couple more microservices. having a single persistent websocket means we're tracking more sessions than necessary. We also should look into solidifying the service boundaries and tracking down what data comes from where and when.