Fixed exit queue (disc). Modes in menu.

- When a player disconnects from the game, he, and all his team leave
the queue if they were in any.
- You can change the mode again.
- 1vsall is disabled.
- You cant change the mode if you are in queue.
- All teamMode games must have 4 players, so externalPlayers is locked
to true when you select that gameMode.