RGB-W with an Output Expander

[zranger1]

(Built a firmware version that actually does this, just to make sure I could.)

Build your own Output Expander Firmware!

It makes me a little uncomfortable, telling people, “go ye, change what code you will and flash then thine own firmware. Easy!”, when I haven’t done it myself. Even though I theoretically know how, I had never actually worked with the output expander’s firmware. So I’ve made a project based on @Wizard’s latest open source that builds alternate firmware for the Output Expander, and describes (here and in the README.MD) how I got there. (Note that this is not intended as a contest entry, just …