Small update to README and add preliminary ReleaseNotes

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Update french translation for release 3.0.0

Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>
Signed-off-by: Kévin Raymond <shaiton@fedoraproject.org>
Signed-off-by: Jean-Noel Rouchon <jnoel@sissiou.net>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>