Aggregate stats from all cluster nodes and publish

Change-Id: Ic41cdcc8fc17845dabffc42b817b8bb7439a0b52
diff --git a/api/src/main/java/org/opencord/dhcpl2relay/DhcpL2RelayStoreDelegate.java b/api/src/main/java/org/opencord/dhcpl2relay/DhcpL2RelayStoreDelegate.java
new file mode 100644
index 0000000..3ff6a49
--- /dev/null
+++ b/api/src/main/java/org/opencord/dhcpl2relay/DhcpL2RelayStoreDelegate.java
@@ -0,0 +1,24 @@
+/*
+ * 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
+ */
+
+package org.opencord.dhcpl2relay;
+
+import org.onosproject.store.StoreDelegate;
+
+/**
+ * Store delegate for DHCP L2 Relay store.
+ */
+public interface DhcpL2RelayStoreDelegate extends StoreDelegate<DhcpL2RelayEvent> {
+}