Handles additional config file

This patch adds the ability to add an additional config file.
The intended use is to have a different variable values for deployment.

The first use case is for the 'url' config variable. Creating an
additional _config-deploy.yml file with the deployment URL, one can
transparently use development and production URLs.
Adds documentation

Added documentation about the _config-deploy.yml feature
Added titles in README and a small blurb describing what is jgd for.
Typo

Fixed typo.
Fixes another typo

Rule 1 : don't commit before coffee
Merge pull request #4 from leucos/deployment_config

Handles additional config file