On my way to my first patch, need review

[vincent]

Even though I don't know if I am accepted for GSoC yet, I thought it would be nice to start contributing now! :) 

I started by adding the gem wayback_machine_downloader (a very useful piece of software by the way). 

So I used `guix edit ruby` and I copied it in the Documents folder. Then I added somewhere in the middle of the file: 

(define-public wayback-machine-downloader
  (package
    (name "wayback-machine-downloader")
    (version "0.2.1")
    (source
      (origin
        (method url-fetch)
        (uri (rubygems-uri
               "wayback_machine_downloader"
               version))
        (sha256
          (base32
            "1nrwm5bc7vqm02m2x0lylxyya446kg0spg6ksi7dfkrad0l9jq8y"))))
    (build-system ruby-build-system)
    (arguments
       `(#:tests? #f ; no rakefile
              ))

    (native-inputs
     `(("ruby-rake-compiler" ,ruby-rake-compiler)
       ("ruby-minitest" ,ruby-minitest)))

    (synopsis
      "Download website from archive.org's Wayback Machine")
    (description
      "Download any website from the Wayback Machine.  Wayback Machine by Internet Archive (archive.org) is an awesome tool to view any website at any point of time but lacks an export feature.  Wayback Machine Downloader brings exactly this.")
    (home-page
      "https://github.com/hartator/wayback-machine-downloader")
    (license expat)))


Then I ran: `guix package -i wayback-machine-downloader -f ~/Documents/ruby` and it successfully installed. 

So my questions are: 

1) Do you guys and gals have a better workflow that includes the git repo, so I can send a patch? All I saw in the documentation was about building guix itself. I guess I could clone somewhere and use `guix package -f`,  but will this be a reliable way of testing? And will this make my guix less stable on the long run?

2) Should I add "ruby-" before the name of the package? I know technically all gems should have "ruby-" before the name, but this is designed to be use independently. Could it have multiple names, or is it a bad idea?

3) Where does this package belong in the directory?

4) Is the package declaration itself all right? Are packages sorted or organized in any way?

5) I speak fluent French, can I add a description and summary in French?

Thanks!
Vincent