Collapsing Buildings Library

It knocks buildings down at a certain speed!

Updates: Accidentally forgot to include both demos on the last update.

Update Version 1.2: Added in some new procs, including a get_height() proc, get_tier() proc, and a Pre_Collapse() proc. Also added a new (but slightly bad looking) demo on how to make (bad looking) waving buildings before they collapse. I didn't have enough time to write a proper algorithm.