This was always used with 'consoleplayer' which really is the only thing making sense here. But this is a part of the global state which should be avoided in play code.
In particular, this makes no real sense in case of secondary maps where it should always return false.
The Map loader may not access any global state at all - everything it can touch must be exchangable.
Furthermore, if we want to sandbox each level, there may be no direct access to any kind of global state whatsoever from the play code.
- offloaded key list generation for alternative HUD to non-UI parts.
This change also revealed a problem with handling empty sprites in the key list so this got fixed, too.
- replaced Key.KeyNumber with special1. This is only for internal bookkeeping purposes so there's really no need to complicate this with a new variable when this one works just as well.
It's about time this stuff is getting cleaned up seriously. Both a_pickups.cpp and a_artifacts.cpp are so overstuffed that it has become a chore finding stuff in there.
