Urban Combat Damage Model Overhaul

As discussed on the forums:
# UC.PassThrough on buildings would calculate the chance of PassThrough as before, taking SubjectToTrenches into account.

# We would have a flag UC.DamageDistributionRatio=##% on weapons which would determine the percentage of damage the primary damage venue receives, e.g. if you had UC.DamageDistributionRatio=70%, and the PassThrough case applied, then 70% of the damage would go to one of the occupants, while the remaining 30% went to the building. If PassThrough did not apply, 70% of the damage would go to the building, while the occupants would get 30% of it. Set to 100% (the default), this would result in the distribution as it is now - either damage the building, or an occupant.
Since, logically, 0% would actually mean "damage the exact opposite in full", which is kind of silly, I could make 0% a special case that never damages occupants, and always sends the full damage to the building.

# UC.DamageMultiplier and UC.FatalRate would remain, so even if only a fraction of the damage makes it through, the bullet could still land a lucky hit, or the shelter's make could still reduce the damage to the occupant further.

# If there is a CellSpread greater than 1, apply Damage/(CellSpread * OccupyHeight * SmallSideOfFoundation) damage to the highest possible number of occupants below (CellSpread * OccupyHeight * SmallSideOfFoundation). iow: Distribute the damage over a simplification of the area it covers, and see how many occupants could fit in it.

# Assaulter and its new brother UC.ClearBuilding would kill all occupants regardless of damage distribution.

##### ADDITIONAL INFORMATION #####
See http://forums.renegadeprojects.com/showthread.php?tid=1469&pid=15437#pid15437
No flag names are fixed until this actually gets implemented.

If you plan on suggesting changes to this issue, please be aware that these plans are already the result of a community discussion, and, as such, any argument for a different implementation should be well-founded and convincing.