Support to inject external bridge into k8s node for external routing

1. Add group bucket related rules on receiving endpoint events
   rather than POD events.

Change-Id: I1152343cf8ff6bbccaed3dc34908a3affbc70980
diff --git a/apps/k8s-node/api/src/main/java/org/onosproject/k8snode/api/K8sNode.java b/apps/k8s-node/api/src/main/java/org/onosproject/k8snode/api/K8sNode.java
index 2c539f3..6dfbead 100644
--- a/apps/k8s-node/api/src/main/java/org/onosproject/k8snode/api/K8sNode.java
+++ b/apps/k8s-node/api/src/main/java/org/onosproject/k8snode/api/K8sNode.java
@@ -69,6 +69,13 @@
     DeviceId intgBridge();
 
     /**
+     * Returns the device ID of the external bridge at the node.
+     *
+     * @return device id
+     */
+    DeviceId extBridge();
+
+    /**
      * Returns new kubernetes node instance with given integration bridge.
      *
      * @param deviceId  integration bridge device ID
@@ -77,6 +84,14 @@
     K8sNode updateIntgBridge(DeviceId deviceId);
 
     /**
+     * Returns new kubernetes node instance with given external bridge.
+     *
+     * @param deviceId external bridge device ID
+     * @return updated kubernetes node
+     */
+    K8sNode updateExtBridge(DeviceId deviceId);
+
+    /**
      * Returns the management network IP address of the node.
      *
      * @return ip address
@@ -169,7 +184,7 @@
         Builder type(Type type);
 
         /**
-         * Returns kubernetes node builder with supplied bridge name.
+         * Returns kubernetes node builder with supplied integration bridge name.
          *
          * @param deviceId integration bridge device ID
          * @return kubernetes node builder
@@ -177,6 +192,14 @@
         Builder intgBridge(DeviceId deviceId);
 
         /**
+         * Returns kubernetes node builder with supplied external bridge name.
+         *
+         * @param deviceId external bridge deviceID
+         * @return kubernetes node builder
+         */
+        Builder extBridge(DeviceId deviceId);
+
+        /**
          * Returns kubernetes node builder with supplied management IP address.
          *
          * @param managementIp management IP address