More editing flags

PSX-inspired flags to change the render styles of monsters (and other
things).
Less flags, more generic properties
Updated documentation
CANRAISE state definition

CANRAISE state for allowing a monster to be resurrected without an
infinite frame
Merge branch 'master' of https://github.com/Edward850/zdoom
Merge branch 'master' of https://github.com/rheit/zdoom