Render cube using vertex and fragment shaders

This gives us nice access to alpha per particle
Make on and off use shader API properly
Sketch out corners example
Since axes are zero indexed subtract one within the cube API
Make it possible to set individual leds

Corners example works now.
Make regular on and off work again

Still need to define how to adjust brightness (alpha).
Inject functional utilities to sandbox in a more reliable way
Clean sandbox properly before execution

Better not to have old stuff laying around there. Just causes confusion.