warn when redshift is active

[klaernie]

I know that this might be a stretch, but could you please implement a check that warns the user when saving a profile, that redshift is currently active?

My ask would be, that if the gamma values are not ̀1.0:1.0:1.0` autorandr checks if a redshift or f.lux instance is currently running, and if so print a warning message.

I was annoyed at redshift for the last couple months, because I switched gpu-outputs and saved my autorandr profile while late at night. This means my profile got a gamma saved, which I didn't intent at all. Just now I spend over 2 hours trying to finally find out, why my system behaves this annoyingly, but of cause it was user error.

Taking a look at the issues I see at least 2-3 instances, where people already stumbled on this unintended effect, so I think this error is common enough to warrant a check if the current gamma is out of balance.

Thanks and kind regards, Andre