Implement kubevirt floating IP's class, codec, watcher and APIs

Change-Id: I2111902e86083add8a00af62557fac1e98b7e7fc
(cherry picked from commit e48a617ccaf19d0d29ccc3211f6254be5e26826e)
diff --git a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/codec/KubevirtRouterCodec.java b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/codec/KubevirtRouterCodec.java
index 4937535..d8529f6 100644
--- a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/codec/KubevirtRouterCodec.java
+++ b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/codec/KubevirtRouterCodec.java
@@ -57,7 +57,7 @@
 
     @Override
     public ObjectNode encode(KubevirtRouter router, CodecContext context) {
-        checkNotNull(router, "Kubevirt router pool cannot be null");
+        checkNotNull(router, "Kubevirt router cannot be null");
 
         ObjectNode result = context.mapper().createObjectNode()
                 .put(NAME, router.name())