rubocop fixes

[vanhecke]

I was reading through the code because I'm planning production use.
Did some easy changes to make rubocop happier.

[namelessjon]

Hi there! Thanks for the patch

What Rubocop settings did you use for this?

[vanhecke]

I'm running linter-rubocop in atom.
Opened the atom package's source and it uses default settings: https://github.com/AtomLinter/linter-rubocop/blob/master/index.coffee