More death functionality.

Death function now accepts stuff like:
"death_function":["NORMAL", "ZOMBIE"]

The dies mtype variable is now a vector of pointers to death functions. All get called on death.

A zombie needs both the normal and zombie tag. Added.

Checked the dinomod. But no changes where needed.

Added a bile blood tag, and fixed the acid blood tag. Both are different effects from boomering and acid exploding. Corpses can now be acid. So when smashed they leave acid pools.

Added ZOMBIE and NORMAL to the spitter. So the spitter leaves a corpse again. (But it dissolves rapidly. But explodes into a 3x3 acid pool if smashed).