Make openbadges Heroku-able

Not sure if you folks care or not, but I deployed openbadges to a Heroku dyno to test something out, and this is what I reconfigured to make it work (primarily I just added in some env vars so they could be setup/used on the Heroku end, and I added a Procfile). I could write up some simple steps for setting up the dyno as well.

May not be of interest to you, but figured i'd share!