pass the command name from HelpCommand
pass the command name from HelpCommand

When the help command instantiates another command class to get its help
text, it needs to pass the command's name if the class supports it.

Change-Id: I3507f723dc8b4e68db80d6da053be61026823457
Signed-off-by: Doug Hellmann <0798ebecfb7bc4dfb9d0445c2fa030eb64e1fa1c@doughellmann.com>

dtroyer/cliff,openstack/cliff,dtroyer/cliff,openstack/cliff