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
Former-commit-id: 5c60566f2d4a9c65fc0fe677841a34d7ef73549a
Former-commit-id: 56497c61fa8403b489c1fc7ca45a9d2e964a4e10