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.
I don't know if that is the pythonic way of doing it, but I think a specific object for installing each module is better from an OO POV. This allows you to have a context you can associate with the current module being installed.