Fix an error when blanking a common anode display.

Signed-off-by: Russell Steicke <russells@adelie.cx>
Make brightness levels in tap states consistent.

This turns out to be a very simple change, due to the way that all the
taps we're concerned about lead us into one state.

Signed-off-by: Russell Steicke <russells@adelie.cx>
After the final roll, hold steady before the flash.

Signed-off-by: Russell Steicke <russells@adelie.cx>