Implement tournament mode

[Kaffeine]

Proposal:

• 16 players: 8 humans and 8 zombies
• The teams defined before the round starts.
• The infected or killed humans join the specs (those specs should not be able to spy on the another team characters).
• Swap teams (humans <-> zombies) each round.
• The longer survivor human team wins.

Probably:

• All different classes.
• As players play different/specific classes, the zombie players should be able to choose the class (before the round starts)
• Some game random should be replaced with static values (scientist white hole, etc).

Maybe's:

• 4 rounds per map.
• "each tourney could have like 6 maps in the pool maybe with a banning system"

TODO:

• Define the conditions for zombie super classes (ghouls, ghosts, undeads, witches)
• Decide what to do with medic revival.

I see those tournament games similar to ctf/tdm games in terms of organization (probably a team don't need a leader and can be formed from players wanted to play together).

Depends on #17