Feature rachel

This PR adds a role for installing rachel that tests for rachel content in /library/rachel before enabling.  It includes en and fr menu items

In the process several config files in /etc/xsce have been re-factored:

xsce.conf is now xsce.env for sourcing into scripts

the old /etc/sysconfig/xs_installed_services is combined with install information such as branch, commit and date, and moved to xsce.ini

An old known problem remains that ajenti is not started or enabled.

on 64 bit vbox vm it completes the install, passes all automated tests except ajenti, and the console works.