ekr, this is how you want to index 2D arrays
Remove picture rectangle.

The picture is always at the top-left of the frame, and the frame size is not
exposed to the API consumer anymore. `frame_width` and `frame_height` are now
in `od_state`.
Add test-driver to ignores.
Move doc git ignores to main ignores and add tools/Makefile.
Don't ignore all makefiles.