PortNumber fixes

- hide new PortNumber(short) and use PortNumber.uint16 instead
- added utility to get PortNumber

Change-Id: Ia39fbe6e7126a3d9465d3035a06850c1d54a7f25
diff --git a/src/main/java/net/floodlightcontroller/core/internal/Controller.java b/src/main/java/net/floodlightcontroller/core/internal/Controller.java
index 23d61bb..dd063a6 100644
--- a/src/main/java/net/floodlightcontroller/core/internal/Controller.java
+++ b/src/main/java/net/floodlightcontroller/core/internal/Controller.java
@@ -614,6 +614,7 @@
             FloodlightContext bContext)
             throws IOException {
         Ethernet eth = null;
+        // FIXME losing port number precision here
         short inport = -1;
 
         switch (m.getType()) {