Doom: Added compatibility option "game-objects-gibcrushednonbleeders"

In the original game any crushed object will be turned into a pile of
gibs irrespective of whether said object is a monster or some other
entirely non-fleshy entity, such as a barrel.

Doomsday fixes this bug/oversight by default and will only gib mobjs
whose Thing definition does not specify the MF_NOBLOOD flag.

This behavior is now compatibility optioned (also modifiable from the
Options > Gameplay menu).