local_offset does not work correctly with non-integer values

[JamieMackenzieUoA]

The local_offset variable makes an adjustment to the 'hours' value in any timestamps that are recorded. However, many locations have a half hour offset (0.5) and this is not accounted for by also adjusting the 'minutes' value.

Additionally, from my reading of the code, I don't believe there is any adjustment being made to the date when local_offset results in a day shift forwards or backwards.