Code for closing Issue 44 [1], which was first developed by Danilo
(@dnr2) and for some reason had disappeared from the source code.

Our current definition of "most used language" relies in the byteCount
of the language in the given project.

Changes to this decision can be addressed probably by changing the
comparation logic in the Language class (which implements Java's
comparable interface).

Closes #44

[1]: https://github.com/spgroup/groundhog/issues/44
[2]: https://github.com/spgroup/groundhog/commit/3339d1567041cbc8926728fe777588d3d8d2b1c5