Merge: gmp: Introduce Long and Ratio

Signed-off-by: PatrickBlanchette <PatrickBlanchette@users.noreply.github.com>

Pull-Request: #2508
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>
Reviewed-by: Jean Privat <jean@pryen.org>
Reviewed-by: Alexandre Blondin Massé <alexandre.blondin.masse@gmail.com>
Reviewed-by: Jean-Christophe Beaupré <jcbrinfo.public@gmail.com>