* Search popup + autocomplete for bones, vertex groups, etc. This
is done with layout.item_pointerR, specifying an RNA collection to
take the items from. Used by constraints and modifiers.
* Some tests with the List template, ignore those for now..
* Menu and header more complete now.
* Clean up Game Properties panel and moved View Properties panel
to python.
* Fix some drawing issues when combining tiles, repeat and aspect,
some also from 2.4x, these options didn't work together 100%.
* Started porting over to python, menus nearly done, header WIP.
* Game Properties panel is in python too
* Deprecated "Tiles" as a per face flag here, now it's always on
the image, used to be both, working in a very confusing way.
Unlikely someone actually had a purpose for this being per face.
* Remove GPC_PolygonMaterial.cpp/h, it's not actually used anymore,
so I don't want to bother updating it.
* Fix crash in image painting (own mistake in porting over bugfix
from 2.4x).
