Update / fix french translation

[AnaelMobilia]

No description provided.

[lieser]

Thanks for improving the translation, before I merge this two comments:

• I'm unsure if you noticed, but the french translation is currently incomplete/outdated. First missed update was for version 4.1.0, what happened since when can be seen e.g. in https://github.com/lieser/dkim_verifier/issues?q=is%3Aissue+label%3Alocalization+is%3Aclosed. Adding the missing once is not required for this to be merged and it is up to you if you want to work on that too.
• In case you decide to also add the missing strings, let me know if you are interested in taking over the maintenance of the french translation.

[AnaelMobilia]

@lieser Thanks for the notice!
I will review all missing translation equally and send a full translation update.

OK to take over the french translation!

Thanks,
Anael

[AnaelMobilia]

@lieser I made change (and squash) to previous commit in order to have a global review of the translation + update FROM 4.1.0 to 5.5.0 version ;-)
It took the liberty to update translator name on options.html, I can revert and/or change if it's not correct!

Bests regards,
Anael

[lieser]

Thanks a lot for updating the translation and being whiling to maintain it. Your changes and the updating of translators LGTM,

I also updated https://github.com/lieser/dkim_verifier/wiki/Contribute#translations.