Refactored logic to pull CBD from the Workshop by calling
the new get_workshop_cbd.sh script rather than using internal
code. So auto_test_cbd_vagrant.sh once again pulls CBD, but
does so using the new script.
The test_cbd.sh script is no
longer responsible for pulling CBD (though the capability
could not easily be added if needed).
Added '-p bin/cbd' call to the Helix Installer SDP reset
script, to preserve the installed CBD directory.