TE Topoplogy subsystem I2RS API changes

This submission contains the following:

1. Major changes in apps/tetopology. The changes are mainly introduced
   to support new searching keys in TE Topology.

2. Add RESTCONF notification support in the TE Provider. i.e., for
   south-bound RESTCONF communication with the domain controller.

Change-Id: I6786959deb66c98626edc65ff52694dcf08981a3
diff --git a/apps/tetopology/api/src/main/java/org/onosproject/tetopology/management/api/TeTopologyService.java b/apps/tetopology/api/src/main/java/org/onosproject/tetopology/management/api/TeTopologyService.java
new file mode 100644
index 0000000..40c8025
--- /dev/null
+++ b/apps/tetopology/api/src/main/java/org/onosproject/tetopology/management/api/TeTopologyService.java
@@ -0,0 +1,161 @@
+/*
+ * 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 org.onosproject.event.ListenerService;
+import org.onosproject.tetopology.management.api.link.NetworkLinkKey;
+import org.onosproject.tetopology.management.api.link.TeLink;
+import org.onosproject.tetopology.management.api.link.TeLinkTpGlobalKey;
+import org.onosproject.tetopology.management.api.node.NetworkNodeKey;
+import org.onosproject.tetopology.management.api.node.TeNode;
+import org.onosproject.tetopology.management.api.node.TeNodeKey;
+import org.onosproject.tetopology.management.api.node.TerminationPointKey;
+import org.onosproject.tetopology.management.api.node.TtpKey;
+import org.onosproject.tetopology.management.api.node.TunnelTerminationPoint;
+
+/**
+ * TE Topology Service API.
+ */
+public interface TeTopologyService
+        extends ListenerService<TeTopologyEvent, TeTopologyListener> {
+
+    /**
+     * Returns a collection of currently known networks.
+     *
+     * @return a collection of networks
+     */
+    Networks networks();
+
+    /**
+     * Returns the network identified by its network identifier. if no
+     * network can be found, a null is returned.
+     *
+     * @param networkId network id in URI format
+     * @return the corresponding network; or null if not found
+     */
+    Network network(KeyId networkId);
+
+    /**
+     * Updates the network.
+     *
+     * @param network network to be updated
+     */
+    void updateNetwork(Network network);
+
+    /**
+     * Removes the network corresponding to the given network identifier.
+     *
+     * @param networkId network id in URI format
+     */
+    void removeNetwork(KeyId networkId);
+
+    /**
+     * Returns a collection of currently known TE topologies.
+     *
+     * @return a collection of topologies
+     */
+    TeTopologies teTopologies();
+
+    /**
+     * Returns the TE Topology identified by the given key.
+     *
+     * @param topologyKey the given TE topology Key
+     * @return the corresponding TE topology
+     */
+    TeTopology teTopology(TeTopologyKey topologyKey);
+
+    /**
+     * Returns the merged topology in MDSC.
+     *
+     * @return the merged topology
+     */
+    TeTopology mergedTopology();
+
+    /**
+     * Creates or Updates a TE topology based on the given topology.
+     *
+     * @param teTopology the given TE topology
+     */
+    void updateTeTopology(TeTopology teTopology);
+
+    /**
+     * Removes the TE Topology identified by its key. Does nothing if
+     * no topology is found which matches the key.
+     *
+     * @param topologyKey the TE topology key
+     */
+    void removeTeTopology(TeTopologyKey topologyKey);
+
+    /**
+     * Returns the TE node identified by the given node key. If no TE
+     * node is found, a null is returned.
+     *
+     * @param nodeKey the TE node key
+     * @return the corresponding TE node,or null
+     */
+    TeNode teNode(TeNodeKey nodeKey);
+
+    /**
+     * Returns the TE link identified by the given TE link key. If no
+     * TE link is found, a null is returned.
+     *
+     * @param linkKey the TE link key
+     * @return the corresponding TE link or null
+     */
+    TeLink teLink(TeLinkTpGlobalKey linkKey);
+
+    /**
+     * Returns a tunnel termination point identified by the given tunnel
+     * termination point key. If no tunnel termination point is found,
+     * a null is returned.
+     *
+     * @param ttpKey the tunnel termination point key
+     * @return the corresponding tunnel termination point
+     */
+    TunnelTerminationPoint tunnelTerminationPoint(TtpKey ttpKey);
+
+    /**
+     * Returns the network Id for a TE Topology key.
+     *
+     * @param teTopologyKey the TE topology key
+     * @return value of network Id
+     */
+    KeyId networkId(TeTopologyKey teTopologyKey);
+
+    /**
+     * Returns the network node key for a TE node key.
+     *
+     * @param teNodeKey a TE node key
+     * @return value of network node key
+     */
+    NetworkNodeKey nodeKey(TeNodeKey teNodeKey);
+
+    /**
+     * Returns the network link key for a TE link key.
+     *
+     * @param teLinkKey a TE node key
+     * @return value of network link key
+     */
+    NetworkLinkKey linkKey(TeLinkTpGlobalKey teLinkKey);
+
+    /**
+     * Returns the termination point key for a TE termination point key.
+     *
+     * @param teTpKey a TE termination point key
+     * @return value of termination point key
+     */
+    TerminationPointKey terminationPointKey(TeLinkTpGlobalKey teTpKey);
+}