added node-config and refactored tc-server-auth to use it.

@indytechcook, @gaitonde 

I wanted to get config in before I ran the s3 challenge,   Lets spend 5 minutes on this tomorrow.
You can either do it this way or add the custom-environment-variables file per: https://github.com/lorenwest/node-config/wiki/Environment-Variables#custom-environment-variables