Add support for all Roland MDX models
Created by: s-ol
Hello!
Somewhere between fabmodules and mods, support for other mills from the roland MDX series got lost. The differences between them are minimal, so I modified the Roland MDX-20 module to support all of them with a model <select>
tag. The values are all taken from the original fabmodules source.
Due to the current health situation I cannot access my lab and verify that everything works, so I would suggest this PR stay open until that is properly verified.