Added -Z option to write out WQ port to a file.
Added -Z option to man page.
Modified SAND tests to use -Z for selecting a port.
Removed find_free_port from the testing infrastructure: the technique has an inherent race condition.
More descriptive test names.
Merge pull request #99 from dthain/master

SAND Test Cleanup
Improved navigation of /cvmfs in the Parrot-CVMFS driver.
It now shows the list of filesystems that can be configured.
Along the way, cleaned up the debug output of the driver
to be more consistent with other Parrot drivers.
Comment clarifying the use of remove_unready_workers().