French translations.

Gracefully contributed by the Qt team @ Developpez.com

Authors:
    Alexandre Laurent <lw.demoscene@googlemail.com>
    Thibaut Cuvelier <dourouc05@gmail.com>
    Guillaume Belz <guillaume.belz@free.fr>

Change-Id: Id1db663fd2cdf820bba62f4b490755731d786a49
Reviewed-by: Pierre Rossi <pierre.rossi@gmail.com>
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
Reviewed-by: Thibaut Cuvelier <dourouc05@gmail.com>
Reviewed-by: Alexandre Laurent <lw.demoscene@googlemail.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>