creds now use env vars; more consistent formatting and var names

[michaelchadwick]

I changed the main db/user/pass variables to use environment variables, to keep them out of the code (seemed like a minor security improvement).

I also went through and made the formatting of lines more consistent as per spacing, comments and such (got rid of tabs, too). I changed the order of cred variables to be more consistent, as well.

Hope this makes the project a little better!