Create jsonschema and check the enums with it

[rom1504]

See http://json-schema.org/ and https://www.npmjs.com/package/jsonschema

The point of this is to check automatically the json format documentation (see https://github.com/PrismarineJS/minecraft-data/wiki/Recipe-format) is actually true and can be trusted, even if recipes.json is updated or if the format change.

It would be nice to add this test to a ci service (circle ci ?)