Whitelist/Blacklist of buildings for Task Garrison

[Zman6258]

Title. While setting up garrisons, there may be cases where players might want to garrison AI in specific locations (such as with CBA's "AI building position" object, or near sandbags placed within buildings) that may overlap with other structures. It'd be incredibly helpful to allow mission makers to specify either a whitelist or a blacklist (ideally both as options) of building classnames.

[nk3nny]

Interesting idea. Might be outside the scope for 2.5

-k