This is NOT True and Robust RGBW Handling™, but does allow easy setting of the W element of RGBW NeoPixels without having to unpack() a previously-pack()ed result. The pack() function accepts an optional W value, in which case it returns a 4-tuple that can be used with the NeoPixel() setter. This is esoteric but the need for it is discussed in issue 25, due to the way the CircuitPython NeoPixel setter works (tuples are preferred to packed ints). This provides a relatively benign quick compromise without having to implement a whole CRGBW class.