behaviour of violent/aggressive animals

[mimo]

we have 4 categories: wild_violent (e.g. lion, tiger), wild_aggressive (e.g. crocodile, wolf), hunt_violent (none) and hunt_aggressive (e.g. bear, boar) currently, only hunt_aggressive have a non zero vision range (=10m) and may thus attack units inside this range. Futhermore, UnitAI has a different behaviour between aggressive and violent: violent animals always attack units within their vision range while aggressive animals only attack then when roaming, so a small fraction of the time.

This should be improved by adding a vision range to all these categories, and deciding if the different behaviour between violent and aggressive is wanted. If yes, the losRangeQuery should be reset each time the animal goes in ROAMING state to properly work.