master is now protected

[pedrospeixoto]

Hi,

Commits to master can now only be done via pull requests.

I suggest a "clean-up" commit to remove user specific codes. However, please feel encouraged to commit anything you find others may find useful. This should not a clear production code (at the moment), but a development code on it own, so we really want small contributions in. Things like the Petropolis benchmark scripts and input files are really welcome, as others may get ideas from those. Just keep them in specific folders, as they already are.