Seperate curve controls for sunrise and sunset

[djurny]

In the morning i like the lights to be as dim as possible, before sunrise and have the lights simulate a sunrise when sun is rising outside. But at sunset, i like the lights to gradually dim over the length of the evening until a predefined time (e.g. bedtime).
The currently available controls apply to both sunrise and sunset at the same time, so it's either a 'steep' curve at sunrise and sunset or a slow curve at both times.