Rewrite config to use toml

[orvitpng]

This rewrites config related files and the majority of main.rs in an attempt to cleanup the code, make it more robust, and allow for toml usage, which is more appropriate for Rust.

[Cormanz]

I'd just like to make a note that you may have to do some additional work to align this with #28 once it is merged.

[orvitpng]

We'll see who finishes first :)