app music updates for 4.2.0 release candidate

- [x] add sfx to Juggler
- [x] add sfx to Boing Ball
- [x] new Run BASIC app framework
- [x] update TC2048 emulator
- [ ] add music to Slideshow
- [ ] add music to VDP Test
- [ ] update music in Skyfall
- [ ] add music to 2019
- [ ] add music to Kayahara
- [x] new Help app (markdown viewer)
- [x] new Locale app (outputs `/system/preferences/system.prf`)