Defer support

[JacobMountain]

An initial attempt at adding @defer directive support #133. Similar to the apollo spec, although currently without the specified line ending CRLF + "-----" + CRLF . I still have to integration test this.

Additional Links

1. GraphQLJava @defer example

[JacobMountain]

I'm not sure if apollo client currently has @defer support. Waiting on apollographql/apollo-feature-requests#3

[oliemansm]

@JacobMountain The defer tests are failing for me. I've marked them ignore for now. Can't imagine they are working for you. Any idea what's going on?

[JacobMountain]

@oliemansm very interesting, I just triple checked my feature branch and they were working still. I will have a look on develop

[JacobMountain]

@oliemansm why are the original async request tests ignored too? maybe the problem is related

[oliemansm]

@JacobMountain Not sure actually... But probably is related, yes. Will try them later as well, but if you have any idea what's wrong that would be helpful :)

[oliemansm]

@JacobMountain Found something. It's a recent PR that got merged that serializes directly to the writer, but that closes something apparently leading to the next elements not being serialized correctly. Problem was in the onNext of the ExecutioNResultSubscriber that was changed.

Probably still issues with async, but at least part of it is solved now.