Blender Git Loki

Scripts:

Misc updates to the ac3d importer and exporter:
- use Mesh instead of NMesh;
- properly export modified data and materials from either ob or obdata (thanks for mesh.getFromObject :) );
- option to export local rot and loc info;
- better import / export of hierarchies;
- + tiny updates here and there to support old or weird .ac files.