Thread polling moved out of midi::alsa and into midi::device.
Added latency measure feature to midi::device.
Improved midi::alsa device lookup time with alsa_device_t.clientIdToDevIdxMap[].
Added cwMidiAlsa.h to provide an interface for midi::alsa independent of midi::device.
cwMidiDecls.h midi::msg_t now breaks out MIDI channel from status and has a new user 'uid' field to link the msg to an external entity.
Renamed midi::packet_t. cbDataPtr to cbArg.
midi::packet_t.cbFunc_t is now included in cwMidiDecls.h.
Other files effected: cwIo.cpp,cwIoAudioMidi.cpp,cwIoPresetSelApp.cpp