Blender Git Loki

BGE: "Fix" for issue [#33663] "Objects Share Materials / Textures When Grouped In SingleTexture / MultiTexture Mode" reported by Josiah Lane (solarlune).

This commit adds a UI option in the Render properties to enable the new material caching in the converter. This caching can cause problems with Singletexture and Multitexture materials when texface is being used to handle materials. By default this option is enabled and users with broken games have two options:

1) Fix up their materials so they are properly using textures
2) Disable the material caching and take a speed hit during conversion time

Regardless of the setting, caching is always enabled for GLSL materials.