Up Blender compatibility version number.
Delete wrong code insert.
Clean up some unused commented code.
Review file format issue with exr and tga extensions.
Refine 'def poll' function for texture image world cases
Rename AA properties_yaf_AA_settings.py to prop_AA_settings.py
Rename yaf_scene.py to tby_scene.py
Apply file name changes.
Change load from file option for Zdepth cases.
Fix checkSceneLights function error with Blender 2.72b
Clarified some description tooltips.
Fix sphere lights size from lamp distance Blender value.
Delete commented code.
Refine 'def poll' for fix error on output panel.
Refine mat use nodes cases.
Merge branch 'rc2' of https://github.com/TheBounty/Blender-Exporter into 0.1.6_rc1