Check for remaining data with Zulu zone (#31)

* Add tests specific to ParseISOZone, UnexpectedCharacterError is now as value for comparison. Check Zulu time does not have remaining data (#30). Fix typo in ErrRemainingData

* Check for zero length zone in ParseISOZone

Add ParseInLocation (#28)

* Add ParseInLocation

* Ensure ParseInLocation overrides input location hint with explicit Zulu time; ParseISOZone supports Zulu (Z) time.

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Co-authored-by: Jason Kingsbury <jason@relva.co.uk>

Better ISO 8601 parsing (#26)

Adds support for YYYY-MM

Permit only year component in date, resolves #21 (#23)

Update README to point to v1 releases (#16)

Time Range Validation (#9)

* Validate time according to standard library

* simplify daysIn by using daysInMonth array

* test invalid range on month 13

* add note about leap seconds

Specifically disallow timezones of "-00", "-00:00" and "-0000", per s…

…ection ISO8601 section 3.4.2. (#8)

ParseString + Go module + Updated Readme (#5)

* updated README, added go module, added ParseString method