Blender Git Loki

Property Search: Improve interaction with panels

This isn't perfect yet, but the animation is back, and it works much better.
There are still two issues though:
1. Order doesn't update sometimes while searching / ending search.
2. Panels are still displayed when empty in some situations.
The solution is probably just adding some more special cases. Possibly
a tag for panel aligning when the search filter is changed to force special
ordering calculations.