Provide sunset/sunrise times as a value

[deckerego]

Use a trigonometric algorithm to compute sunrise/sunset values based on lat/lon given through the weather observation library.

[deckerego]

https://math.stackexchange.com/questions/2186683/how-to-calculate-sunrise-and-sunset-times

[deckerego]

https://maas.museum/observations/2007/10/30/how-to-calculate-sunrise-and-set-a-worked-example/