correct invalid category


git-svn-id: https://svn.blender.org/svnroot/bf-extensions/trunk/py/scripts/addons@4320 96b784f8-4ae3-dd11-aff7-0030488c597c
Rigify: bug fix: certain kinds of import errors were being suppressed in
rig types.


git-svn-id: https://svn.blender.org/svnroot/bf-extensions/trunk/py/scripts/addons@4321 96b784f8-4ae3-dd11-aff7-0030488c597c