Fixes for recent changes in 483350 (ohnet API changes)
Changed OhmSender so that the zone and uni/multicast threads don't get started if the interface is set to 0.
Updated due to api changes in ohnet 46229e1
More changes due to ohnet api change in 46229e1
Define custom debug levels rather than relying on ohNet providing them
Fix leaks in OhmMsgFactory
OHM wireshark plugin:
- Removed check which assumed that multicast Songcast
  packets are always sent to port 51972.
- Display the right name (OHM or OHU) in the Protocol column.
Keep Songcast tests from crashing.