unsigned PortNumber

PortNumber class update
- internal representation now uses int
- toString() now converts the value as unsigned integer
- renamed value() to shortValue()
- added value() method returning port number as unsigned long
- added constructor from String
- JSON serialization now uses the new value(), so that special handling for
  unsigned integer is not required

Update classes using PortNumber
- Replaced value() calls with new value(), when the return value was
  converted to long immediately.
- toString() result may change if the object contained PortNumber.
  - e.g., FlowEntryAction, FlowEntry, SwitchPort, ...

Change-Id: I0b1f8aa92208e165b6113c8dd6954076c0513167
diff --git a/src/main/java/net/onrc/onos/core/hostmanager/HostManager.java b/src/main/java/net/onrc/onos/core/hostmanager/HostManager.java
index fd34519..ff3ee8c 100644
--- a/src/main/java/net/onrc/onos/core/hostmanager/HostManager.java
+++ b/src/main/java/net/onrc/onos/core/hostmanager/HostManager.java
@@ -283,7 +283,7 @@
                 deleteHost = new Host(host.getMacAddress(),
                         null,
                         switchPort.getDpid().value(),
-                        (long) switchPort.getNumber().value(),
+                        switchPort.getNumber().value(),
                         new Date(host.getLastSeenTime()));
                 break;
             }