JSON output of swagger-diff -i

[dodalovic]

Hi, thanks for your fantastic tool, first of all!
Small question from my side: I'd like to use this tool from another tool, that would expect that output of

swagger-diff -i old.yaml new.yaml

would be json formatted.
I believe there's no way to control that right now? Is it something that makes sense?
I'm unfortunately not a ruby developer, and can't contribute with PR :(

Cheers