QuadMIDI needs converting into Seaboard

[danpetry]

• diff my changes and apply them to v0.6.

• take files which represent my changes (before/after) and place them in a directory

• apply the diff to the files

• make it into 8 outputs instead of 4

• edit the user interface using the tips here https://vcvrack.com/manual/PluginDevelopmentTutorial.html#panel

• make the changes to the source code required to handle changes to the UI.

• debug

[danpetry]

Needs to identify by channels rather than note, so it handles cc messages properly