hjsonschema is deprecated

[seagreen]

I apologize for doing this. I'm no longer interested in JSON Schema, and hjsonschema's serious flaws mean I don't want to recommend it to anyone anymore.

You can read more details in the README: https://github.com/seagreen/hjsonschema#deprecation-notice

[dredozubov]

Thanks for telling me this. I'll get to it once it'll start to be an issue with schematic

[dredozubov]

While working on schematic with @ak3n we've experienced some false positives in validation and tracked this issue down to the hjsonschema library. I don't really see a good substitute for a library right now, maybe it makes more sense to make a small subset that will be enough for schematic and implement within the library itself.