v17.1 / v18 Roadmap

Note: that preference is for all changes to be opt-in and available on the v17 line, anything BREAKING will be delayed until v18.

The below is my wishlist, please feel free to comment here

- validateSchema => parallel rules via mapSchema/visitSchema
- #2873
- directive validation
- #3222
- #4816
- full SDL validation?
- framework for standardizing that all rules have programmatic/SDL analogues ?
- hard split between separate graphql modules? i.e. use `IGraphQLSchema` interface in modules outside `type` instead of class `GraphQLSchema`
- #4442 ? perhaps at least get rid of main barrel file
- execution experiments
- #4760
- #4769
- #4776
- type safety
- #2188