- can pass a context so graphql schema can check that
- we use the context to determine what user is currently logged in
- the context is a decoded jwt payload in request.user.
"graphql": "0.5.0", "graphql-relay": "0.4.1", "express-graphql": "0.5.1",
express-graphql at version 0.5.1 required to be able to check context variable