This supports level shifters that invert the data
Config option - "invert" (integer)
if omitted, do not invert
if == 0, do not invert
if !=0, invert
Former-commit-id: 44ab64329641f0e1450174314a955d241641d149
Add a new WS281x driver which is a wrapper around jgarff's ws281x library which
works on Pi B+, Pi 2, Pi Zero and probably Pi 3 as well.
jgarff's ws281x library is included as a submodule
Former-commit-id: e473dfd36d31b14598da5e56e4b8bf9f2aa7bb24
