I'm submitting a ... * [x] feature request PostGraphile version: 4.7.0 I want to enable [this functionality](https://github.com/graphql/graphql-js/pull/1141) but looks like we can't currently control parser [options](https://github.com/graphql/graphql-js/blob/master/src/language/parser.js#L64) It would be nice if postgraphile could do this