adds cli subcommand for dumping configs in application.yml to STDOUT

[TheNotary]

Here's a feature for just dumping application.yml data into a format that one can easily do say export DUMP_RESULTS or place into a setup_env.sh file.

What do you think? (relates to #222)

Update:
Oh sorry for leaving such a hasty PR, I'm in the middle of a bunch of devops stuff on a tight time schedule. I wrote this feature out to work as a stand alone listing of ENV vars like A="a" B="b" but you can also add switches to make it easy to set configs on heroku-like platforms dokku config:set APP_NAME A="a" B="b"