Facilities handle decoration

Make facilities handle their own decorations and hook up most of the FS code to go through them instead of manipulating the underlying variables by hand.

@Blank_Alt - work off of this for !9499 (merged). I haven't done a lot of testing on it, and I'm sure I've missed a bunch, but it should give you the right idea and the tools to expand. And I'm pretty sure it doesn't break anything at this point.