Further work on 3DS target animations.
FixNormals-Step inverts face order now.
Further work on the doc to aiCamera.h, added helper function to get a view matrix.
git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@312 67173fc5-114c-0410-ac8e-9d2fd5bffc1f