fix base defense error

and clean up defenses when we're done.
and ... adulterate

Merge branch 'master' of https://github.com/SupSuper/OpenXcom into oXc_kL
Conflicts:
	src/Battlescape/DebriefingState.cpp
	src/Geoscape/BaseDefenseState.cpp
	src/Geoscape/BaseDefenseState.h
	src/Savegame/Base.cpp
	src/Savegame/Base.h