MRG: ALL now merges PRG CHG, AT, PITCHWHEEL and CHANNEL PRESSURE
MRG: ALL now merges PRG CHG, AT, PITCHWHEEL and CHANNEL PRESSURE

This closes #23

wesen/mididuino,wesen/mididuino,wesen/mididuino,wesen/mididuino,wesen/mididuino,wesen/mididuino