get in sync with railsgirls and add tokaido tutorial

Hey we're gonna need the guide for RailsGirls Lyon so I updated it with railsgirls/master and brushed up the translation.
Main addition is Tokaido, the self-contained Mac app by @wycats.

added a TODO file also, (I may work on translations in the future) you can get rid of it if you want.

I moved everything in a lang-fr branch, I think it's cleaner to keep master as the railsgirls/master because it won't be merged upstream anyway.