[ONOS-2718][ONOS-2722][ONOS-2723] Fix three bugs of vtnweb.

Change-Id: I4dc631c879e1a7239ce1538289cea51d903ddb50
diff --git a/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java b/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
index 1bcb291..64266a5 100644
--- a/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
+++ b/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
@@ -94,7 +94,7 @@
     public Response getportsById(@PathParam("id") String id) {

 

         if (!get(VirtualPortService.class).exists(VirtualPortId.portId(id))) {

-            return ok("the virtualPort does not exists").build();

+            return ok("The virtualPort does not exists").build();

         }

         VirtualPort virtualPort = nullIsNotFound(get(VirtualPortService.class)

                 .getPort(VirtualPortId.portId(id)), VPORT_NOT_FOUND);