Code cleanup

As a light exercise for a Sunday evening, I've made some code clean up involving mainly the removal of unused imports, stale looking code/comment parts, and some trivial PEP8 changes (adding/removing white spaces).

This PR builds on #47, since a significant amount of code was removed in that. Once that one is merged, I'll rebase this one to make the review easier.
Is there a reason to keep this line?