* Update CLUO from v0.4.1 to v0.5.0
* Earlier versions of CLUO fail to drain nodes on Kubernetes 1.9
so nodes drain one at a time repeatedly and Container Linux OS
updates are not applied to nodes.
* Check current OS versions via `kubectl get nodes --show-labels`
* Add a reboot-coordinator namespace for CLUO components
* Define an RBAC ClusterRole for update-operator and update-agent
* Replace the older-style where CLUO ran in kube-system, with
admin privilege
