- 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.
# Conflicts:
# src/g_shared/shared_hud.cpp
- 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.