Replace sun to moon if night time

[R11baka]

Resolve #68

[R11baka]

@schachmat Maybe I send many commits to this PR.

[schachmat]

Heyho @R11baka,

Thanks again for your great work! There was already an attempt at this issue in PR #88, but there were still 3 points missing. You managed to tackle the first two already. I'd be happy to merge your PR if you handle the last one as well, adding night-alternative icons for every condition code where a sun is visible currently. It would be a little inconsistent if you have a moon displayed in the CodeClear condition at night, but if the next night has the CodePartlyCloudy there would still be a sun hiding behind clouds. ;)

[schachmat]

Oh and an implementation hint.

Just copy the codes := map[iface.WeatherCode][]string map and name the existing one codesDay and the new one codesNight. You should be able to assign the existing images for cases where there is no sun/moon displayed like iface.CodeCloudy: codesDay[iface.CodeCloudy],

[R11baka]

@schachmat If I understand correctly, I should replace codeSunny, partly rainly,partly cloudly,partly light rain ?

[schachmat]

@R11baka,

There is a sun visible in:

• CodeHeavyShowers
• CodeHeavySnowShowers
• CodeLightShowers
• CodeLightSleetShowers
• CodeLightSnowShowers
• CodePartlyCloudy
• CodeSunny (renamed to CodeClear in your PR)
• CodeThunderyShowers
• CodeThunderySnowShowers

They might seem like a lot, but since the sun is clipped equally in most of them, replacing the sun with a moon should not be too hard.

[R11baka]

Hi @schachmat . Created new pull request
#117