adds all the coding for MP5K
to note, some things like the spread, recoil and kick are copied from the MP40, so they may be inaccurate, and might need to be changed in the future
Make all wall weapons fullbright to fix visibility issues. Properly
precache W_BOWIE assets. Use grenade_bag.mdl instead of grenade world
model when using the grenade weapon.
Adds some utility functions to make grabbing specific pieces of weapon
information in any of a player's slots easier. Fixes some mulekick bugs
as a side effect. Fixes https://github.com/nzp-team/nzportable/issues/52.