Feature: Need a Brightness- button

[davepl]

At some polnt the "Brightness Down" button, second from the left in the top row of the remote, next to ON) used to dim the brightness. If you hit ON, it would set to max brightness and pin the effect on.

I think the top two buttons should be Brite- and Brite+ and I prefer that Brite+ just goes to max brightness, not steps up. But we need to move the "SET_EFFECT_INTERVAL to MAX" feature to another button, one of the spare buttons in the lower right.