Added application that adds a topology overlay displaying additional statistics of links.

Change-Id: Ie82ce67ead64b9b62d6ab55f3ef8ac0f62946d9f
diff --git a/apps/linkprops/src/main/java/org/onosproject/linkprops/LpLinkMap.java b/apps/linkprops/src/main/java/org/onosproject/linkprops/LpLinkMap.java
new file mode 100644
index 0000000..f840f44
--- /dev/null
+++ b/apps/linkprops/src/main/java/org/onosproject/linkprops/LpLinkMap.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2017-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
+ * limitations under the License.
+ */
+package org.onosproject.linkprops;
+
+import org.onosproject.net.Link;
+import org.onosproject.net.LinkKey;
+import org.onosproject.ui.topo.BiLinkMap;
+
+/**
+ * Our concrete link map.
+ */
+public class LpLinkMap extends BiLinkMap<LpLink> {
+    @Override
+    protected LpLink create(LinkKey linkKey, Link link) {
+        return new LpLink(linkKey, link);
+    }
+}