Fix components for fur blanket and fur sleeping bag

Closes #1271.
Let the player see recent messages on death

Closes #1303.
Make surface slime pits ot_slimepit_down, as was presumably intended originally
Stop ot_slimepit_down from appearing on the lowest z-level
Set known_down on ot_slimepit_down, and unset it on ot_slimepit
Fixed erronious "destination area full"
First aid actually is not an antibiotic.
Arm and Leg Splints

More or less a place holder for when Medical Treatment is expanded.
Today's batch of bugfixes and improvements.