Add "Lobby" functionality to nadron

[menacher]

It is a common requirement to have a Lobby room which is a special gameroom that has list of other game rooms. Users first login to this game room and are then connected to the actual game room later on.

Lobby room will generally be passing back metadata about the rooms it holds, for e.g. number of players in each room, unique name of the rooms, geographic location and so on. Probably it can be a json string thats sent back to client.

[MaksimShakavin]

And how can i the disconnect from lobby and connect to another room?