Pely: online rooms in test

Pely was built for one couch and four people on it. The most common request
since the first beta has been the obvious one: let us do that when we are in
different cities.

Friends-only rooms are now in test. Create a room, send the code, play all
twelve modes exactly as they play locally. No matchmaking yet, and that is on
purpose: we would rather get four known people in a room working perfectly
before we try to find you strangers.