nuke: clear test firewall rules

Signed-off-by: John Spray <john.spray@redhat.com>
daemon: add DaemonGroup.resolve_role_list

Used for tasks that want to take a flexible list
of roles from their user config, including a
null (everything) default and * wildcards.

Signed-off-by: John Spray <john.spray@redhat.com>
orchestra: fine tune docstrings.

Signed-off-by: John Spray <john.spray@redhat.com>
orchestra: more docstring

Signed-off-by: John Spray <john.spray@redhat.com>
Merge pull request #299 from ceph/wip-7810

Wip 7810