Redo README for ruby example
Redo README for ruby example

heroku/heroku-buildpack-pgbouncer,Yobota/heroku-buildpack-pgbouncer,Shyp/heroku-buildpack-pgbouncer,agriffis/heroku-buildpack-pgbouncer,rmoorman/heroku-buildpack-pgbouncer,realtymaps/heroku-buildpack-pgbouncer,BetterWorks/heroku-buildpack-pgbouncer,gregburek/heroku-buildpack-postgresql,musicglue/heroku-buildpack-postgresql