Cleanup and debloat the lib

[KOLANICH]

This library requires requests. Do I really need requests in order to validate a local json schema? Are remote refs resolved with requests a security hole?

I guess we need a smaller and non-bloated jsonschema lib.

[Julian]

I neither agree with your premise nor your entitled tone -- that's not the right way to file an issue on any project.

Please do feel free to find something else if this library doesn't make you happy.