* Renamed from material shapes to textures shapes
* No per-texture, so the same material can use different shapes with different textures
* Load a shape image instead of text file with vector components
* Allow texture sizes that are not multiple of the map zoom
* Add minimum overlap parameter to draw shapes only when the given overlap is reached.
This should simplify insertion of new textures at arbitrary drawing orders without reassigning palette indices (the latter would invalidate all old maps).