Add kolla-kubernetes bootstrap capability to Keystone

Kolla-kubernetes requires there be an alternative way to bootstrap
the container. Kolla-kubernetes needs to signal the Kubernetes API
endpoint to make the cluster aware a bootstrap is in progress.

Partially-implements: blueprint kolla-kubernetes-extended-dockerfiles
Change-Id: Ie078017496eec81188d4c7c7916a70d1722f8aee