Add comparison chart to documentation

[unoexperto]

Hey guys,

I found out about your set of libraries because I recently switched to doobie. Could you create comparison chart that compares fs2-http and akka-http (both client and server side) ? I'm long time user of spray (now akka-http) but I'm always interested if any new frameworks/libraries come up.

[pchlupacek]

sure, we may add that to readme. Any specific feature you looking for ?