Pontoon: Update French (fr) localization of AMO
Pontoon: Update French (fr) localization of AMO

Localization authors:
- kko <kko.firefox@pinedaserna.org>
- goofy <goofy@babelzilla.org>
- corentin.jacquet <corentin.jacquet@telecomnancy.net>

diox/olympia,mozilla/olympia,mozilla/olympia,psiinon/addons-server,diox/olympia,eviljeff/olympia,wagnerand/addons-server,diox/olympia,bqbn/addons-server,wagnerand/addons-server,mozilla/olympia,diox/olympia,bqbn/addons-server,wagnerand/addons-server,mozilla/olympia,eviljeff/olympia,psiinon/addons-server,bqbn/addons-server,eviljeff/olympia,bqbn/addons-server,wagnerand/addons-server,mozilla/addons-server,mozilla/addons-server,psiinon/addons-server,mozilla/addons-server,psiinon/addons-server,mozilla/addons-server,eviljeff/olympia