eg.
for v in me.verts: print(v.index)
added calc_edges as an option eg.
mesh.update(calc_edges=True)
This is needed when adding faces to an existing mesh which create new edges.
Seems to have been a copy+paste error (code for Vertex Color adding was pasted in place of texture paint). Restored the code from an earlier revision (from another file).
* Move mesh API functions to mesh_data.c, would like to keep
RNA layer fairly thin, any non-trivial functions shoud be
in their modules.
* Replace mesh.create_copy by generic id.copy.
* Fix#19250: Mesh.add_geometry() in editmode fails silently,
now gives an error.
