Minor adjustments to alien health icons.
Fixed aliens hissing when they were doing their regular emotes.
Added death sound to aliens.
Aliens can now properly attack/interact with space carp.
Adjusted alien damage to monkeys.
A few wip sprites.
Fixed pulse rifles, again.
git-svn-id: http://tgstation13.googlecode.com/svn/trunk@729 316c924e-a436-60f5-8080-3fe189b3f50e