Add callback to the plethora of retry halting possibilities

Change-Id: Idb5a2158f008b41133352dcfb4926ad21dcceea1
Signed-off-by: Saggi Mizrahi <smizrahi@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/8093
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>