Added namespaces to the cluster, creds and context in set_kubeconfig
Added namespaces to the cluster, creds and context in set_kubeconfig

Without a namespace based on the bosh environment, clusters given the
same name will collide with one another and users must re-run
set_kubeconfig every time they wish to switch between a cluster. With
the namespaces, that should reduce the likelihood of a collision and
allow users to switch using `kubectl config use-context <context-name>`.

[#152752429]

pivotal-cf-experimental/kubo-deployment,pivotal-cf-experimental/kubo-deployment,jaimegag/kubo-deployment,jaimegag/kubo-deployment