Add node IP attribute in k8s node class with minor code refactoring

Change-Id: I4c1c86c95acfeb38569b91c1677e4ce8af90460f
diff --git a/apps/k8s-node/app/src/test/resources/org/onosproject/k8snode/codec/K8sMinionNode.json b/apps/k8s-node/app/src/test/resources/org/onosproject/k8snode/codec/K8sMinionNode.json
index fb01b77..ca78a90 100644
--- a/apps/k8s-node/app/src/test/resources/org/onosproject/k8snode/codec/K8sMinionNode.json
+++ b/apps/k8s-node/app/src/test/resources/org/onosproject/k8snode/codec/K8sMinionNode.json
@@ -5,6 +5,7 @@
   "segmentId": 100,
   "managementIp": "172.16.130.4",
   "dataIp": "172.16.130.4",
+  "nodeIp": "172.16.130.5",
   "integrationBridge": "of:00000000000000a1",
   "externalBridge": "of:00000000000000b1",
   "externalInterface": "eth1",