Various updates made

Changes:
-Permissions
-No longer given to OP players (otc.clock excluded - OP players get this
permission)
-Added otc.announce.mod: Announces a moderator's entrance, instructing
players to direct help requests to him or her.
-Added otc.announce.special: Intended for server admins and owners,
allows a customized entrance message to be broadcast. Individual players
may change it using "/otc sa message". Announcements accept formatting
(&1, &2, &3, etc.).
-Cleaned up some of the code.