cloud_cover_to_transmittance_linear function of forecast.py doesn't use passed 'offset' parameter

[KonstantinTr]

Should 'offset' be used instead of 0.75 in the expression?

[wholmgren]

Thanks, good catch. Can you submit a pull request with a new test for this behavior?

[KonstantinTr]

Sure. I'm new to git so it'll take some time to get how to do it :)

[wholmgren]

closed by #348.