Load rules after service start
Load rules after service start

congress-server fails to re-start if there exists some action rules
as the rules are loaded before the engine service start. This
commit also registers the datasource service immediately after
loading the driver to avoid any errors incase polling starts
before respective service is started.

Closes-Bug:#1585563
Change-Id: I3b8046fe5d863784b426dd3f71ee46f83119d3ff

ramineni/my_congress,openstack/congress,ramineni/my_congress,ramineni/my_congress,openstack/congress,ramineni/my_congress