Implement JSON schema serialization/deserialization

[MaggieKimani1]

With the full adoption of JSON schema in v2.0, we need to update our v31 deserializers to emit a valid JSON schema instance as well as our internal YAML writer to properly format all the keywords contained in the resulting JSON schema during serialization.

[MaggieKimani1]

Closing this as its superseded by #1727