Make the kson test suite runnable from other languages

[aochagavia]

In our initial conversations about kson bindings for other languages, we thought we might get away with a few smoke tests, since the kson library itself is already thoroughly tested. On hindsight, I think we should run comprehensive tests for each of our bindings, since there is plenty that can go wrong in the FFI code and those errors are high-risk (the whole program crashing, memory corruption, and nasal demons). For example, my generated python bindings were randomly crashing the interpreter because of an FFI issue, without any error message whatsoever.

I'm not too deep into the kson test suite, but I assume the best way forward here is to express relevant tests in a language-agnostic manner (e.g. as plain text input and output files). That way we can easily load them from another programming language (e.g., Python) and test the bindings thoroughly.

[dmarcotte]

Agreed. I have some ideas around this I'm looking forward to discussing and fleshing out together in real time.