- made HasFooBar()-checks more precise on the way
- cleared up everyone's destructors to also delete arrays if the corresponding mNumFoo member was zero. This hopefully does not break all too much
- Bugfix: meshes without bones now properly show up with DisableMaterials enabled
git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@230 67173fc5-114c-0410-ac8e-9d2fd5bffc1f