AWOL users + spooky speak changes + author disable

AWOL Users will make Polkabot's "left whilst in a game" message useless. This checks for users that left the channel but never returned before the game ended. If a user returns, nothing is printed. Reduces spam for people with bad connections.

Spooky Speak (dead chat) can now be toggled on and off, if you were already able to see it. good for players who just want to watch the game without commentary.

Authors can now disable their own themes. Requested feature, many people supported.

Themes cannot be removed while being played now to prevent errors during phase changes (this has only happened once, and Beast + I know not to do it again, but just in case!)

Cleaned up the very lengthy commands list... Though in reality it grew by 1 line...