Blender texture script improvements

[ghost]

After having used your excellent script for Blender/Cycles post-import fixes, I have made a few changes.
The main loop logic to iterate directly on textures in order to avoid same textures being processed again, and most important, make the logic work even if you don't export with the "1 object per material" option.
Now I tested successfully with either j-mc-2-obj configurations:

• 1 object for whole export
• 1 object per material
• 1 object per block

[paol]

Thanks!