Add a simple display & encoder to v4 revision

[sejerpz]

What's your opinion about adding a simple display and an encoder to the hardware?

[GuitarML]

I probably won't be adding a screen, I had a specific layout in mind when designing the Funbox. There is another great project that has a screen/encoder that I've used, so a screen in this project seems redundant to me, here is the other project:

https://github.com/bkshepherd/DaisySeedProjects

If someone did want to add a screen to FunBox, they'd probably need to either use a bigger enclosure, or design a board with smd components instead of through-hole.

[sejerpz]

Thanks for the link, but soldering smd is too much for me :)

Funbox is such a great a simple design but I'd like to have more options to display info to the user beside just the two leds.