Fix imports to match new structure in the files copied from Raspberry Pi. Add missing imports in macbeth.py. Add missing dependencies to requirements.txt. Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>