Fix: sbd-integration: sync pacemakerd with sbd

Make pacemakerd wait to be pinged by sbd before starting
sub-daemons. Pings further reply health-state and timestamp
of last successful check. On shutdown bring down all the
sub-daemons and wait to be polled for state by sbd before
finally exiting pacemakerd.
Add new api as not to make the xml-structure an external interface.