Translating the documentation to french

[Siltaar]

I created a pull request with the quick syntax reference translated in .fr.adoc files.

#806

I'm open to discuss about it if needed ^_^

[mojavelinux]

Thank you for your contribution! This is fantastic.

Now, I have to share some information that hopefully doesn't throw too much of a wrench into this. We are in the process of migrating the documentation to Antora (see https://github.com/asciidoctor/docs.asciidoctor.org). That mostly entails breaking the user manual up into discrete pages and moving the pages out of the asciidoctor.org repository and into the software repositories (e.g., asciidoctor/asciidoctor). (Although I've been making changes to the user manual recently, I've been porting those changes to the migrated site. That's not as easy to do with translation.)

To avoid duplication of effort, what I recommend is waiting until we have the docs migrated, then bring over the French translation as a follow-up step. But we certainly want to keep the branch open since that's what we'll take the files from.

We will need to determine where the French files go in the new structure. But this gives us an opportunity to think about it. The main documentation is going to live in asciidoctor/asciidoctor. Should the French translation live there too? It seems to make sense. Another option is to have a separate repository per translation. That allows the translations to track the upstream, but not get caught up in the release cycles for them.

cc: @graphitefriction

[Jibec]

For external readers, I commented directly the pull request with how Fedora community handle this very same subject: #806