Closes#16146
While in there, modified the testing infrastructure for the help text
so that we can get commands with nested commands - like "volume".
Signed-off-by: Doug Davis <dug@us.ibm.com>
For both commands, volume is _not_ optional. Several volumes may
be specified.
Both commands now use the same name (VOLUME) for the command argument.
Signed-off-by: Harald Albers <github@albersweb.de>
