Dismemberment [Needs testing] 

Sorry about having to make a clean PR.

Admin button to change limb types
You can now dismember peoples limbs!
MELEE DISMEMBERMENT
GUN DISMEMBERMENT
Augmentation reworked to be nicer using this system
Augmentation surgery reworked to be a limb removal surgery
A Bunch of useful procs for future projects involving organs/limbs
drop_both_hands() proc which calls left and right hand dropping procs for you
The less limbs you have the slower you walk (if you survive with no legs you can CRAWL with your arms)
Adds human_parts.dmi which was produced by Nienhaus
Unused human mutantrace SPRITES have been added for admin fuckery
Perhaps some other things I forgot
fixes #2738 - Cheers @Incoming5643

DON'T MERGE UNTIL:

I've tested things [In progress]
I've implemented a way to get the augments/replacement limbs