Add version info to MMA and MIDI

[Karim Ratib]

Right now, we produce a comment Generated by musicxml-mma converter https://github.com/infojunkie/musicxml-mma in the MMA script but we need to add the following for better traceability:

• A version number (will require reading package.json from XSL)
• Ensure this comment makes it all the way inside the MIDI file