fix operand in fallState
fix mistake in die state re: exposure

shouldn't really matter, but safe > sorry
fix certain damage types passing through walls

most noticably stun damage, but also incendiary and smoke.
fix ctrl+alt+kill function
make tank/cannon article consistent with other HWPs
game doesn't end when missions run out.

had to remove references in favour of making copies, because reasons.
Merge pull request #20 from SupSuper/master

sync