Tidy up and refactor

Some old puppet style was showing in this module, and it was actually a bit _over-factored_. For a module of this size, splitting out the repo, package, and service actually ends up being overkill and makes scanning what the module does more complicated than it needs to be.

I've pulled the `repo`, `package`, and `server` classes into the top-level class, leaving `configuration` out on its own to make dependency management easier. I then renamed the latter to `config` for consistency with other modules.

Some minor style things were tidied up in the process, too.