Rewrite setup.py to integrate more with distutils and setuptools

This is just an experiment I did some time ago and that I updated today with the recent changes to setup.py. I tried to integrate more with distutils and setuptools by using subclasses of distutils.cmd to do the specific actions related to our project (e.g. compiling/installing mo-box and the translations) that are not handled by setuptools directly.

This should allow us to specify better the dependencies among commands, to run a single command (i.e. "compile only the translations") and to easily implement an uninstall command for CMS.

Give it a look, and perhaps a try. We can discuss if this approach is better than the one we have now.