This moves review into a separate permission, aside from "server".
The benefit is that we can grant this to more people without the
need to pass out "server" privs, which has a lot more powers than
needeed.
This doesn't grant noclip. This needs to be done separately. Scoring
will be disabled for those with the review priv.
Some of these are copies from the respective origins from mtg,
to make sure we have headers everywhere listing the proper code.
I've relicensed spectator_mode from WT*PL to LGPL-2.1. No other
licenses were changed.
