Merge pull request #60 from YoheiKakiuchi/master

IGNORE_UP_DIRECTION for not transforming point of vertices
Fixed a bug returning not all material properties when accessing them.

Also fixed another bug occouring when no normals are provided in sample.py (lists do not have a any() method).
Merge pull request #62 from faulesocke/master

Fixed a bug returning not all material properties when accessing them.
Fixed a bug in the bugfix -.-
Merge branch 'master' of github.com:assimp/assimp
Merge pull request #63 from faulesocke/master