Polar twilight icons

[bergmorten]

What about icons symboling polar twilight (Polar twilight occurs in areas that are located at the inner border of the polar circles, where the Sun will be on or below the horizon).

E.g. similar to the symbols uses by the Yr Icons Api, a horizontal line above the icon: https://api.met.no/weatherapi/weathericon/2.0/documentation

[fox91]

Hi @bergmorten,
would you like to make a PR with these new icons?