More code cleanup, better exception handling, use of package names as counter namespace,

src/main/java/net/floodlightcontroller/core/IOFSwitch.java

...main/java/net/floodlightcontroller/core/OFSwitchBase.java

...va/net/floodlightcontroller/core/internal/Controller.java

...a/net/floodlightcontroller/debugcounter/DebugCounter.java

...oodlightcontroller/debugcounter/IDebugCounterService.java

...t/floodlightcontroller/debugcounter/NullDebugCounter.java

.../java/net/floodlightcontroller/debugevent/DebugEvent.java

...tcontroller/devicemanager/internal/DeviceManagerImpl.java

...ntroller/linkdiscovery/internal/LinkDiscoveryManager.java

...va/net/floodlightcontroller/topology/TopologyManager.java

src/main/java/org/sdnplatform/sync/internal/SyncManager.java

...lightcontroller/devicemanager/test/MockDeviceManager.java