Remove microprofile-sandbox/proposals/streams

[hutchig]

If James is happy with it I will remove the folder at
https://github.com/eclipse/microprofile-sandbox/tree/master/proposals/streams

as Jame's vision became:
https://download.eclipse.org/microprofile/microprofile-reactive-messaging-1.0-RC1/

and we want to tidy up the sandbox.

I will drop a tag to record a commit where it is present.

@jroper are you OK with this?

[kwsutter]

Thanks for the cleanup operations, @hutchig. Since we have a standalone repo for reactive now, I think this streams sandbox could be deleted (or archived). Is there such a thing as archiving a directory like this? Maybe deleting is the proper way to go.

[t1]

Also graphql is obsolete. It's https://github.com/eclipse/microprofile-graphql now. I'll create a PR.

[t1]

Just created #80