Civil provides Date, Time, and DateTime types.

This package was put together to add support for Json interfaces while maintaining no changes to the upstream package so future updates will flow in easily.

This civil package was originally copied from cloud.google.com/go/civil. The license remains the same.

Support for JSON interfaces (json.Marshal() and json.Unmarshal()) were copied from github.com/openly-engineering/civil. A big thank you for that!