Make AsyncAPI schemas conform to JSON schema

[fmvilas]

As Phil Sturgeon pointed out in his articles (this and this), the divergence between JSON Schema and OpenAPI schema (which AsyncAPI is identical to) is causing some problems.

At this point, given that AsyncAPI is still in its early stages and I'm collecting breaking changes for version 2.0.0, I wonder if it would be a good idea to make AsyncAPI schemas conform to a more recent JSON Schema version (maybe 6 or 7?).

As an addition, we could also implement the alternate-schema keyword proposed here (without the x-oas-draft). But, IMHO, that's another issue.

Thoughts? @MikeRalphson @bpedro @philsturgeon @darrelmiller

[philsturgeon]

That would be amazing, please fully support actual JSON Schema, at least 6 but hopefully draft 7.

There would be an element of "This is just like OpenAPI, but different, we use actual JSON Schema instead of JSON Kindaschema" and then everyone will be fine.

[fmvilas]

I'm closing this issue since AsyncAPI 2.0.0 will support multiple schemas, and therefore any JSON Schema version, including the OAS flavor 🎉

Will update soon but feel free to ask any questions.