[fr] first draft of tech doc
[fr] upgrade vagrant doc
Merge pull request #6 from Marmo/master

Added de-folder and translated en/01_Getting_started.md
change filename
add german language in config file
petite précision
Create 01_Help_wallabag.md
Create 13_Hidden_options.md
Merge branch 'master' of https://github.com/wallabag/documentation
add french documentation
[en] 1st draft for hidden options
[en] contribute to wllbg