Remove unnecessary geolocation from Night Color KCM
Makes the Night Color KCM not try to geolocate unless needed.
Before:
Night Color KCM attempts geolocation whenever Display & Monitor is opened in System Settings, even if Night Color is off, and/or even if a "Current location" mode isn't selected.
After:
By default, no geolocation is attempted.
If user selects "Manual location" and clicks "Detect location", geolocation starts.
If user selects "Current location", geolocation starts (and then keeps happening regularly). User is informed that the location will keep being updated in the background.
