Add NoteWithDuration class
Add a class that is NoteWithDuration, which is composed of NoteOn and NoteOff and the duration, so that basically it can be used in a script, and possibly used as part of the Sequence class, so schedule NoteOn and NoteOff events rather then having to include both NoteOn and Noteoff in a sequence JSON. Hopefully this would ensure that the NoteOff always happens, Experiment with the idea anyway.
This can't be used for HandleMIDI though since Event NoteOn never knows the duration. So I'm not sure how often this would really be used.