New medical item updates, bandage/first aid refactor

Adds Nickboom's new medical items to spawn lists that seemed appropriate. Cleaned up typos in a few of the descriptions. Added a proper iuse::disinfectant function, and extracted common logic (i.e., most of the functions) from the existing iuse::bandage and iuse::firstaid.

Also, apparently there was code to print the HP totals that would result from healing yourself? It was just printing in an area that didn't technically exist. Moved that so it actually prints inside the window.