Update home page Readme to include setup and general info/benchmarks about Presto

[jaystarshot]

I think the readme on the main github page is important to attract new developers. At the moment, it's quite minimal.
We should add a link to setup guide, and small info about presto, its goals and benchmarks if available

Expected Behavior or Use Case

Presto Component, Service, or Connector

Possible Implementation

Example Screenshots (if appropriate):

Context

[jaystarshot]

cc: @steveburnett