store vector of attackers rather than a bool
ignore merge.

Merge branch 'master' of https://github.com/SupSuper/OpenXcom into oXc_kL
Conflicts:
	src/Battlescape/AlienBAIState.cpp
	src/Battlescape/AlienBAIState.h
	src/Battlescape/ProjectileFlyBState.cpp
	src/Battlescape/TileEngine.cpp