Support additional string formats in typing helper classes

Summary

Support additional string formats built into the JSON Schema spec.

Proposed benefits

A more comprehensive library of reusable typing classes for schemas.

Proposal details

The SDK currently only lists date and date-time strings formats, but there's a handful of other formats that would be useful like email, ipv4, uri, etc.

Best reasons not to build

There aren't any real downsides to adding these 🙂