API definitions for the TE Topology Core App.

This APP creates and manages a hierarchy of TE topologies received from SBI TE provider and from user configurations from NBI.
The API contains internal data structures for TE attributes that are aligned with the TE attributes definition in standard IETF YANG TE topology model (https://tools.ietf.org/html/draft-ietf-teas-yang-te-topo-05).

This commit includes the following interface definitions:
- TE topology provider service, which is called by the TE topology provider from SB to pass TE topologies to the TE topology core APP
- TE topology service, which provides service APIs for an external APP to get/set TE topologies and their attributes.
- Network, Node, Link definitions for TE networks and their default class implementation

Change-Id: Iafcf6911b8d9e494397e3a255cae282bbca74d5c
diff --git a/apps/tetopology/src/main/java/org/onosproject/tetopology/management/api/TeTopologyStore.java b/apps/tetopology/src/main/java/org/onosproject/tetopology/management/api/TeTopologyStore.java
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+++ b/apps/tetopology/src/main/java/org/onosproject/tetopology/management/api/TeTopologyStore.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2016 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.onosproject.tetopology.management.api;
+
+import java.util.List;
+
+import org.onosproject.store.Store;
+
+/**
+ * Inventory of TE network topology.
+ */
+public interface TeTopologyStore
+        extends Store<TeTopologyEvent, TeTopologyStoreDelegate> {
+
+    /**
+     * Returns a collection of currently known networks.
+     *
+     * @param  type TE topology type
+     * @return a collection of stored internal TE networks
+     */
+    List<InternalTeNetwork> getNetworks(TeTopologyType type);
+
+    /**
+     * Returns the network.
+     *
+     * @param  networkId network id in URI format
+     * @return value of internal TE network
+     */
+    InternalTeNetwork getNetwork(KeyId networkId);
+
+    /**
+     * Updates the network.
+     *
+     * @param network value of the network to be updated
+     */
+    void updateNetwork(InternalTeNetwork network);
+
+    /**
+     * Removes the network.
+     *
+     * @param  networkId network id in URI format
+     */
+    void removeNetwork(KeyId networkId);
+
+}