Add the -l option to show the list of tests
Make the default zdtm/live/ prefix when running individual test

Now you can do it like

# sh ./zdtm.sh           for running all tests
# sh ./zdtm.sh -l        to list available tests
# sh ./zdtm.sh <test>    to run test <test>, e.g. "static/pipe00"
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>