A script for cloning a non-relocatable virtualenv.

Virtualenv provides a way to make virtualenv's relocatable which could then be
copied as we wanted. However making a virtualenv relocatable this way breaks
the no-site-packages isolation of the virtualenv as well as other aspects that
come with relative paths and /usr/bin/env shebangs that may be undesirable.

This script attempts to overcome these and other issues and provide a way to
easily clone an existing virtualenv.