Added builder and more logs for VtnService and VtnPort

Change-Id: I52f672caebf1946b9bb01c9de0ca2ad2cee23f69
diff --git a/apps/xosclient/src/main/java/org/onosproject/xosclient/impl/DefaultVtnPortApi.java b/apps/xosclient/src/main/java/org/onosproject/xosclient/impl/DefaultVtnPortApi.java
index a7329d4..8054dfe 100644
--- a/apps/xosclient/src/main/java/org/onosproject/xosclient/impl/DefaultVtnPortApi.java
+++ b/apps/xosclient/src/main/java/org/onosproject/xosclient/impl/DefaultVtnPortApi.java
@@ -119,12 +119,14 @@
                 pair -> addressPairs.put(IpAddress.valueOf(pair.getIpAddress()),
                                          MacAddress.valueOf(pair.getMacAddress())));
 
-        return new VtnPort(VtnPortId.of(osPort.getId()),
-                           osPort.getName(),
-                           VtnServiceId.of(osPort.getNetworkId()),
-                           MacAddress.valueOf(osPort.getMacAddress()),
-                           IpAddress.valueOf(ipAddr.getIpAddress()),
-                           addressPairs);
+        return VtnPort.builder()
+                .id(VtnPortId.of(osPort.getId()))
+                .name(osPort.getName())
+                .serviceId(VtnServiceId.of(osPort.getNetworkId()))
+                .mac(osPort.getMacAddress())
+                .ip(ipAddr.getIpAddress())
+                .addressPairs(addressPairs)
+                .build();
     }
 
     // TODO remove this when XOS provides this information