Stop config-manager as first bundle when shutting down controller

bgpcep is trying to merge:

https://git.opendaylight.org/gerrit/#/c/6089

to it's stable/hydrogen branch. This has a controller prerequisite of:

"3e0009d Stop config-manager as first bundle..."

So the above commit, 3e0009d, needs to be cherry-picked to the stable/hydrogen branch in the controller.