[WIP] Medical Revamp

Reworking of the medical system to give cool junk like broken limbs, missing eyeballs, and possible frontal lobotomies (medically appropriate, I promise, you won't feel a thing). Any and all comments welcome!

Status: Tinkering and Thinking! (sorta just started!)

Todo:
- [ ] Medical class to handle all medical/first aid related things, because game.cpp needs a break. :(
- [ ] Migrate First Aid usage over, as well as consumables/comestibles usage.
- [ ] Think about cool things to implement, like IV infusions, slings, eyeball fixers, those things you play with at the doctor's office that makes your knee do funny things, etc.
- [ ] Make more todo thingies as I come up with junk.
- [ ] Make a couple more things so it seems like I am doing work as opposed to playing cata.

Please don't add headers until they're used, they're a pain to root back out again if they're spread too widely.