Run through Rubocop style checker

This tightens up a lot of whitespace and makes certain kinds of syntax consistent, like blocks and hashes. I set it in Ruby 1.8.7 mode, so the code continues to run on 1.8.7 and up.

It is also more common practice now to name the `version.rb` file at `lib/yourgem/version.rb`. I have a matching change to the gemspec on another branch that I will also submit.