Add support info and project summary to README

I mainly wanted to get the contact/support info into the README.  I also injected a variation of Harvest's tagline.  It's a little more concrete than "The Harvest Stack is an open source BSD-licensed toolkit for building web applications for integrating, discovering, and reporting data".

*If* putting the support info here is a good idea, we probably also want to put it in some other READMEs that first-timers are likely to be working from, e.g. omop_harvest.  Thoughts?

Signed-off-by: Kevin Murphy <murphyke@email.chop.edu>
I hear you.  Personally I would rather change the website description to make it more specific and just link back to it.  
My reasoning for changing the text is that the website tagline is overly vague, and if people are looking at a repo, they might appreciate the kind of specifics that will let them quickly decide whether the repo is relevant to them.  Currently you can't really tell what Harvest is from the front page of the website ....