Implement streaming API

[lino-levan]

This uses EventSource, so we'll probably have to use Skye's polyfill until denoland/deno#14730 lands.

[daimajia]

Hi @lino-levan Thanks for your working on this project. About the EventSource, do this https://deno.land/x/eventsource@v0.0.3 project works in api streaming?

update: i get it. we are saying the same thing. Looking forward to supporting streaming api.

[ChuckJonas]

In the meantime, maybe consider removing the "stream" option from the API interface?

Just wasted quite a bit of time thinking my code handling the stream was buggy, when really this library just crashes if you set stream:true in the options...

[lino-levan]

I'll make a PR today. Sorry for the trouble!

[daimajia]

How is the progress?

[lino-levan]

Sorry for the delay, didn't get around to doing it yesterday. PR is open now, waiting on a review from @load1n9 to merge.