fix buggy win conditions and stats in death01

- Special rooms which stay even when last player quits. Not useful for now, and can't be removed at all. - Define default value for SCRIPT in room config - Allow server admins to join 'registered users only' room

here have some lua love: make parameter count error messages more helpful to lua devs (also: some whitespace cleanups)

lua call SetAmmoDelay(ammotype, delay). note: as the engine does not yet support per-clan/team/hog ammo delay values, lua scripters will have to keep track of individual delays and set them accordingly before a hedgehog's turn (if they want usage cool-down behavior)