Removing inert Wound AEmitters to avoid lag and bad visuals

[pawnishoovy]

Currently wounds just stack up forever, which for doors or other tough objects gets very laggy and ugly-looking.

Current attached Wounds should be limited to a certain number per object, like 20. Active Wounds, that is, emitting AEmitters, should be exempt from removal until they stop emitting.

New property: CurrentWoundCount (or RealWoundCount, etc), which returns only the actual real number of attached Wounds. WoundCount remains an all-purpose "total wounds suffered" count.

Functions that remove wounds should remove first the visual ones, then simply decrement the WoundCount.

This will likely need a little refactoring because WoundCount is probably currently coupled to the number of real attached Wounds. It'll need to be made more abstract.