Add the JSON Schema test suite

[schani]

We should be able to parse all valid test cases.

https://github.com/json-schema-org/JSON-Schema-Test-Suite

[snehaljos]

hi, @schani can I give it a try?

[schani]

Hi @snehaljos! For sure!

There are two main parts to this:

1. You'll have to write a driver (I suggest adding an extra command line option to main in test.ts) that loops through all the JSON Schema test files, and for each test schema in each of the files, run quicktype and produce JS output. It shouldn't crash.
2. Now for each of the schemas, run the JS output on each of the tests that has valid: true. They should all succeed.