feature request: CLI could use file extension to support yaml and json

[toddobryan]

Sometimes, you have a schema in YAML and a doc in JSON or vice versa. Currently, the CLI only supports JSON, I think, but it would be terrific if it could parse YAML or JSON based on the file extension.

[leadpony]

Hello @toddobryan
Thank you for nice suggestion.
Currently Joy must be configured at compile time for parsing files in YAML. Therefore first we need to modify Joy to accept JsonParser flag for selecting YAML or JSON at runtime.

[toolmantim]

Thanks for the great lib and cli!

I recently ran into this while hoping to use the CLI to validate some YAML:
https://gist.github.com/toolmantim/93cd1b877dd2937d51be52d1d132e8ec

It was fairly easy getting it running in Docker like that, but a custom build of the CLI proved to be too hard. A command line flag, or instructions for how to compile a CLI version that supports YAML, would be amazing ❤️