Implement kubevirt node service, expose it through REST API and CLI

Change-Id: Ieebd2652af31344df3a7c91d3669a2ba150cb57f
diff --git a/apps/kubevirt-node/api/src/main/java/org/onosproject/kubevirtnode/api/KubevirtNodeAdminService.java b/apps/kubevirt-node/api/src/main/java/org/onosproject/kubevirtnode/api/KubevirtNodeAdminService.java
new file mode 100644
index 0000000..424a422
--- /dev/null
+++ b/apps/kubevirt-node/api/src/main/java/org/onosproject/kubevirtnode/api/KubevirtNodeAdminService.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.kubevirtnode.api;
+
+/**
+ * Service for administering inventory of {@link KubevirtNode}.
+ */
+public interface KubevirtNodeAdminService extends KubevirtNodeService {
+
+    /**
+     * Creates a new node.
+     *
+     * @param node kubevirt node
+     */
+    void createNode(KubevirtNode node);
+
+    /**
+     * Updates the node.
+     *
+     * @param node kubevirt node
+     */
+    void updateNode(KubevirtNode node);
+
+    /**
+     * Removes the node.
+     *
+     * @param hostname kubevirt node hostname
+     * @return removed node; null if the node does not exist
+     */
+    KubevirtNode removeNode(String hostname);
+}