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
diff --git a/metadata/service/common.yml b/metadata/service/common.yml
index 5e72de2..12f782f 100644
--- a/metadata/service/common.yml
+++ b/metadata/service/common.yml
@@ -2,8 +2,11 @@
 - service.kubernetes.logging
 - service.kubernetes.monitoring
 parameters:
+  _param:
+    kubernetes_cluster_domain: ${_param:cluster_domain}
   kubernetes:
     common:
+      cluster_domain: ${_param:kubernetes_cluster_domain}
       network:
         engine: none
         mtu: 1500