CORD-628 Refactored VTN service network and port API

- Removed direct use of Neutron data model and Neutron API
- Extended service network and service port API to have all network
  information required for VTN
- Removed unnecessary dependency manager and store
- Removed network state sync method with Neutron and XOS
- Removed Neutron and XOS access information from the network config
- Re-organized API packages

Change-Id: I18f49ec733309315f683dfb2e6be6526056118f1
diff --git a/src/main/java/org/opencord/cordvtn/api/core/ServiceNetworkListener.java b/src/main/java/org/opencord/cordvtn/api/core/ServiceNetworkListener.java
new file mode 100644
index 0000000..dc8782c
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/core/ServiceNetworkListener.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.opencord.cordvtn.api.core;
+
+import org.onosproject.event.EventListener;
+
+/**
+ * Listener for service network event.
+ */
+public interface ServiceNetworkListener extends EventListener<ServiceNetworkEvent> {
+}