GitLab

Now compiled locale files (.mo) are generated on the server side.
This cleans up the git tree and make translation contributions much
easier to merge.

Please note that you will need to generate those files after each pull,
so remember to execute install_re2o.sh.

* Rather than using href="\\host/about/" in page footer, use
  href="protocol://host/about/"

* The old footer uses hacks to be staticly on the bottom. To make it
  much simpler one solution is to turn it white and use official
  Bootstrap code. This leads to less CSS to maintain and better
  cross-browser compatibility.

* On re2o about page (/about/) there is some typos such as :
  * assocations > associations
  * legitlab > le gitlab

* Use Bootstrap navbar-static-top rather than custom CSS.
  The result is the same, so we should be better using directly
  Bootstrap CSS.