Fix wrong brightness convertion

XYZ is innacurate and not user friendly, instead use max (R,G,B) to set the brightness.

Change RGB convertion brightness

max (RGB) = brightness
fix strange brightness with some colors.

Add group transition time

v1.7.8

- Add group transistion time

Add brithness control on setRGB for Group

v1.7.7

- Add custom brithness to setRGB to Group

Add brithness control on setRGB (fixed)

v1.7.6

- Add custom brithness to setRGB to be more accurate (RGB : 0 0 255),…

Add brithness control on setRGB

v1.7.5

- Add custom brithness to setRGB to be more accurate (RGB : 0 0 255),…

Update transition on light

v1.7.3

- Add the possibility to update transition time on light object (befo…

v1.7.2

• Temp fix for division by zero in color convertion

First release fork by neoteknic

Bugfixes, extra features, drop old php (before 7) version.