Minutes of negative offset also need multiplier

[pd9333]

Code here: https://github.com/rtfeldman/elm-iso8601-date-strings/blob/3587ff12251261514d0da49837f3c170d0249448/src/Iso8601.elm#L342-L345

Might be:

multiplier * (hours * 60 + minutes)

[jamesrweb]

@pd9333 can you give an example test case to show where utcOffsetMinutesFromParts doesn't work as intended per specification?

[pd9333]

Based on wikipedia, it looks like there are currently only two areas which are using negative offsets and has minutes

UTC offset	Location
UTC−09:30	French Polynesia: Marquesas Islands
UTC−03:30	Canada: Newfoundland, Labrador (southeast)

Take the first one for example. If we try to parse -09:30, the correct value should be -570, but current implementation gives -510

[jamesrweb]

Based on wikipedia, it looks like there are currently only two areas which are using negative offsets and has minutes

| UTC offset | Location |

| -- | -- |

| UTC−09:30 | French Polynesia: Marquesas Islands |

| UTC−03:30 | Canada: Newfoundland, Labrador (southeast) |

Take the first one for example. If we try to parse -09:30, the correct value should be -570, but current implementation gives -510

I will take a look into this later today, thanks for the context!

[jamesrweb]

@pd9333 Opened PR #32 and now it is for @rtfeldman to review and merge. Really nice catch, kudos to you! 🎉

[pd9333]

:bow: