CORE: Added GM hide functionality so that GMs can hide from players and monitor them.
SCRIPT: Added @hide command to allow GMs to hide from players.

Note: Other GMs that are the same or higher rank can see other GMs that hide.
Note: @hide is just a toggled function, it also has '@hide status' to check your hidden status.

Note: GM hidden status DOES NOT save at all. You must manually do it each time you login if you want to hide. This also does not hide you from the search server. If you wish to hide from the search server, use /anon while your GM flag is turned on!