Example in Readme: making a GraphQL request

[bennettscience]

There's some buzz on Canvas working toward releasing more GraphQL APIs, particularly with the New Quizzes API coming in the near future. It looks like that will be a GraphQL endpoint.

I know the library can make GraphQL requests, but an example (for those of us with no experience in making them) would be great along with the other getting started examples.

[jonespm]

Hi @bennettscience

I used this script when I was testing the implementation of this. I verified that this is still working.
https://gist.github.com/jonespm/b8b493da4ef385a60f49ca355a8043c3

I think we've used this call a few times internally as well. I thought it could be cool if this library was able to auto-translate some of the common methods to GraphQL calls instead to improve performance but never got around to working on that.