[FEATURE REQ] Configure gamma per monitor

[asmarcz]

**Is your feature request related to a problem?
I want to configure gamma temperature per monitor since my external monitor has different colour properties.
Describe the solution you'd like
Configure gamma properties per video output.
Describe alternatives you've considered
I have tried using monitor_override but believe it is tied to the sensor config.

[FedeDP]

Hi! Thanks for opening this feature request!
I think it would be a neat idea to rework Clight configuration to have a "monitor" structure with gamma temperatures and backlight curves, thanks for the hint!
I will try my best to provide such a feat in reasonable times given my limited spare time :)