Continue progress on use of external containers.
This PR adds the ability to mount, umount and list the
storage containers whether they are in libpod or not.
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
We should default to the user name unmount rather then the internal
name of umount.
Also User namespace was not being handled correctly. We want to inform
the user that if they do a mount when in rootless mode that they have
to be first in the podman unshare state.
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>