grilo-lua-sources contains sources for the grilo media discovery framework, implementing support for a variety of sources.
Sources that are of good quality and well maintained will eventually be merged into the upstream grilo-plugins repository.
The repository also includes companion libquvi scripts for libquvi 0.9, that will be used by some of the sources to get the media URL, given a web page URL.
A very succint tutorial for grilo's lua sources exists at: http://www.hadess.net/2014/02/extend-gnome-videos-with-lua.html
Each grilo or quvi lua script includes copyright and license information. Please refer to them for more details.