consolidate example documentation

does this seem cool to peeps?  If so, I'll fix up the links in the top-level README.  This would be nice for the blog post, b/c then I could link to https://github.com/KevinCorcoran/trapperkeeper-webserver-jetty9/tree/ring-example-docs/examples/ring_app

There didn't seem to be any good reason why this file should just be the README under the example directory.