Added a devtool add and devtool modify flow digram. Updated
the Makefile to support those figures in the tarball creation.
(From yocto-docs rev: b40692065262dee0209329886b6e3a743c32b1bd)
Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>