Merge: Introduce nitcatalog

nitcatalog is the tool behind http://nitlanguage.org/catalog/

It is a simple hackish program that scan projects and generate the HTML files from various source of information:

* model
* project metadata
* git history

If you want to try it at home, consider also merging #1675

Pull-Request: #1678
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>