Set notification_bind on zaqar websocket
Set notification_bind on zaqar websocket

Don't let zaqar websocket listen to notifications on all interfaces:
otherwise, it uses the hostname as a subscription target, and it doesn't
work when the host is set as an IPv6 host. Ultimately this should be
fixed in Zaqar, but this will work around it for now.

Change-Id: Ib7ece313371660ea02bef314bf5b5d2c4121a884
Related-Bug: #1727406

dprince/tripleo-heat-templates,openstack/tripleo-heat-templates,openstack/tripleo-heat-templates,dprince/tripleo-heat-templates