ONOS-6483 API to check if node exists

Change-Id: I368340bccdfe89a6e95e1068b966acf64b8aa5b4
diff --git a/apps/config/src/main/java/org/onosproject/config/impl/DynamicConfigManager.java b/apps/config/src/main/java/org/onosproject/config/impl/DynamicConfigManager.java
index 9d54e5a..0cda139 100644
--- a/apps/config/src/main/java/org/onosproject/config/impl/DynamicConfigManager.java
+++ b/apps/config/src/main/java/org/onosproject/config/impl/DynamicConfigManager.java
@@ -98,6 +98,10 @@
         throw new FailedException("Not yet implemented");
     }
 
+    public Boolean nodeExist(ResourceId path) {
+        return store.nodeExist(path).join();
+    }
+
     public void registerHandler(RpcHandler handler, RpcCommand command) {
         throw new FailedException("Not yet implemented");
     }