Add the script get-status-stats and a status list

get-status-stats returns status statistics given a csv file generated
by the script get-status-loop and a file containing the list of the
status we want the statistics. The status list contains all status that
can be returned by the script get-status.

Signed-off-by: Kévin THIERRY <kevin.thierry@open.eurogiciel.org>
Scripts to report the status of opened reviews

Also add a list of all available statuses and update the install
script.

Note that the manifest file needs to be updated to document those new
scripts.

There is a bug in the script get-gerrit-status-open which causes
https://review.tizen.org/gerrit/#/c/16751/ not to be processed. This is
probably due to an unescaped character.

Signed-off-by: Kévin THIERRY <kevin.thierry@open.eurogiciel.org>