Add indoors terain type "pool water" for mansion pools

Closes #868
Allow player to change tires with a wrench and a jack (requires 0 mechanical skill but does not skill up). Add "jack" item to mi_hardware and mi_mechanics spawnlists.
Fix desc: hydralic => hydraulic
Remove unused slen variable used in removed keyword coloration kludge
Merge indoor pool fix.
MErge tire changing code.