2 - Log PacketIns with no payload and stop processing
3 - Remove unused IOFController interface

Create NullCounterStore and NullPktInProcessingTime modules. These are used to create a minimal configuration for performance testing or to turn them off.

move updateCounter methods to counterStore, add controller-level packetIn, packetOut, and flowmod counters

Conflicts:

	src/main/java/net/floodlightcontroller/util/TimedCache.java