Add "type" attributes to Topology elements

Add type attributes to Topology elements (ONOS-1575, ONOS-1391)
- add "type" as String attributes
- add "type" to JSON representation

Change-Id: I0ab790cfd18eba17e352780b336e5cd49c6fcb1e
diff --git a/src/main/java/net/onrc/onos/core/topology/web/serializers/PortSerializer.java b/src/main/java/net/onrc/onos/core/topology/web/serializers/PortSerializer.java
index 69d710e..34d411f 100644
--- a/src/main/java/net/onrc/onos/core/topology/web/serializers/PortSerializer.java
+++ b/src/main/java/net/onrc/onos/core/topology/web/serializers/PortSerializer.java
@@ -4,6 +4,7 @@
 import java.util.Map.Entry;
 
 import net.onrc.onos.core.topology.Port;
+import net.onrc.onos.core.topology.TopologyElement;
 
 import org.codehaus.jackson.JsonGenerator;
 import org.codehaus.jackson.map.SerializerProvider;
@@ -26,6 +27,7 @@
         //
 
         jsonGenerator.writeStartObject();
+        jsonGenerator.writeStringField(TopologyElement.TYPE, port.getType());
         jsonGenerator.writeStringField("state", "ACTIVE");
         jsonGenerator.writeStringField("dpid", port.getDpid().toString());
         //