Modules installer

This is a simple modules installer (can't handle multiple files, or requirements yet)

It connects to http://jaspermoduleshub.herokuapp.com/

I added a `walk_packages` on `brain.py` so that modules can be installed in subfolders.
We shoudn't install these requirements automatically. Some users might prefer to do this via their package manager. Also, this requires to run this script with root permissions, which is not so nice. I'd prefer returning a list of unsatisfied dependencies or something like that.