New variable kubernetes_cluster_domain

Use cluster_domain/domain variable consistently across all templated files.
All kubeconfig fields contain cluster domain for uniqueness.

Using kubernetes_cluster_domain param now to allow physical servers
to have a different domain from kubernetes cluster if necessary, but
the default keeps them the same.

Change-Id: Ic1e571dc92166b8b603214367f10382fb0ff04b7
18 files changed