Add quick holstering and unholstering keys

[DrSmugleaf]

About the PR

Fixes #2015
Fixes #2029

Media

• I have added screenshots/videos to this PR showcasing its changes ingame, or this PR does not require an ingame showcase

Changelog
🆑

• add: Added quick holster and unholster keys.

[github-actions]

RSI Diff Bot; head commit 60521fb merging into 342af03
This PR makes changes to 1 or more RSIs. Here is a summary of all changes:

Resources/Textures/_CM14/Objects/Clothing/Shoes/Marines/black.rsi

State	Old	New	Status
filled			Added

Resources/Textures/_CM14/Objects/Clothing/Shoes/Marines/brown.rsi

State	Old	New	Status
filled			Added

Resources/Textures/_CM14/Objects/Clothing/Shoes/Marines/jungle.rsi

State	Old	New	Status
filled			Added

Resources/Textures/_CM14/Objects/Weapons/Guns/gun_underlays.rsi

State	Old	New	Status
_88m4			Added
aamateba			Added
amateba			Added
b92fs			Added
c_deagle			Added
c_xm51			Added
cmateba			Added
cmateba_special			Added
d_xm51			Added
deagle			Added
g_deagle			Added
highpower			Added
highpower_b			Added
highpower_tac			Added
m43			Added
m44r			Added
m44rc			Added
m4a3			Added
m4a345			Added
m4a345_s			Added
m4a3c			Added
m82f			Added
mateba			Added
np92			Added
npz92			Added
ny762			Added
pk9			Added
pk9r			Added
pk9u			Added
s_xm51			Added
smartpistol			Added
spearhead			Added
tt			Added
ttb			Added
vp78			Added
webley			Added
xm51			Added
zhnk72			Added

Edit: diff updated after 60521fb