Add support for brotli

[josenobile]

Brotli is like gzip or deflate, but is becoming more popular. I found this if is useful: https://www.npmjs.com/package/shrink-ray

[ForbesLindesay]

I'm not really actively maintaining this library, but I would definitely be keen to add support for it to https://github.com/ForbesLindesay/http-basic