Add cylon effect

[wridgers]

Example config:

[led_effect bed_idle]
autostart: true
frame_rate: 30
leds:
    neopixel:bed_lights
layers:
    cylon 0.75 1 top (1,0,0),(0,1,0),(0,0,1)

Examples

[julianschill]

Thanks for the contribution. I will take some time until I will be able to test and merge it.