add area_poly_v3_max() for use with area_poly_v3


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@53629 954f8c5b-7b00-dc11-b283-0030488c597c
Add normal_flip() member to Python BMesh's Face.


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@53630 954f8c5b-7b00-dc11-b283-0030488c597c