added that players which moves in the 'back to lobby' cooldown will not be teleported.
added FreeForAllJoinEvent and FreeForAllLeaveEvent.
added settingtype to the kitpvp api.
added editable sign, scoreboard and hologram layout.

improved the performance.
changed a few messages.

fixed that ffa arenas used the same map.
fixed that players without the permission kitpvp.admin can break the join sign.