doc-rst: buffer: numerate tables and figures

Sphinx actually doesn't numerate tables nor figures. So,
let's add a subtitle before each table. That makes them
"numerated".

While here, fix the git binary that got corrupted.
Let's hope this will work, as the reason why we had
to encode them were to prevent some issues on commiting
those gif files on git.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>