DARK           Room is dark.
DEATH          Room is a death trap; char ``dies'' (no xp lost).
NOMOB          MOBs (monsters) cannot enter room.
INDOORS        Room is indoors.
PEACEFUL       Room is peaceful (violence not allowed).
SOUNDPROOF     Shouts, gossips, etc. won't be heard in room.
NOTRACK        ``track'' can't find a path through this room.
NOMAGIC        All magic attempted in this room will fail.
TUNNEL         Only one person allowed in room at a time.
PRIVATE        Cannot teleport in or GOTO if two people here.
GODROOM        Only LVL_GOD and above allowed to enter.
HOUSE          Reserved for internal use.  Do not set. 
HOUSE_CRASH    Reserved for internal use.  Do not set. 
ATRIUM         Reserved for internal use.  Do not set.      
OLC            Reserved for internal use.  Do not set. 
BFS_MARK       Reserved for internal use.  Do not set. 
