Moving private members of Assimp::Importer to a pimpl, hopefully solving strange crashes with vc9 debug builds.
Updating assimp_cmd to reflect these changes.
git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@403 67173fc5-114c-0410-ac8e-9d2fd5bffc1f