some fixes for unconcsious unit revival.

stop them becoming invisible, set their position to null when picked up,
set it when thrown or dropped, and a small fix for "where do i get up" checking.
kill unconscious units when you break their corpses.
- Fixed craft names getting stuck.
- More fixes to target destruction logic.
- Warnings.
wake the aliens up on the right spot.

if you move their unconscious body, or pick it up and carry it around, it will
wake up on the right spot.
get units to move the hell out of the way of falling units.
blander farms, but no more empty map segments.
fixed reapers
fix for severe multiple interceptors following single ufo.
Merge branch 'master' of https://github.com/SupSuper/OpenXcom into artificial_stupidity

Conflicts:
	src/Battlescape/UnitWalkBState.cpp