Accordion

Emulates a three row diatonic or continental chromatic accordion. There is a
choice of midi instruments and keys, including C System and B System.

* Keys: F/Bb/Eb, G/C/F, A/D/G, C#/D/G, B/C/C#, C System, B System
* Instruments: Standard midi set, defaults to accordion
* Choice of one standard 31 button Hohner layout and two 25 button layouts
* Choice of fascia images

Uses Sonivox midi synthesizer for midi audio output.

* Update themes
* Update layouts