fix for UDK FBX files which have smoothing layers with no data.


git-svn-id: https://svn.blender.org/svnroot/bf-extensions/trunk/py/scripts/addons@4699 96b784f8-4ae3-dd11-aff7-0030488c597c
worarounds to get some models for 3dsmax loading


git-svn-id: https://svn.blender.org/svnroot/bf-extensions/trunk/py/scripts/addons@4700 96b784f8-4ae3-dd11-aff7-0030488c597c