Added OFF Loader. Tested with various configurations, seems to work.
Added POLYLINE support to the DXF Loader.
Added WIP version of the MDR loader - disabled and not yet working.
git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@145 67173fc5-114c-0410-ac8e-9d2fd5bffc1f