Update a couple inconsistent commented outputs

Updates `#=>` to `# =>`.

Reasons why `# =>` is preferred:
- used in TRPL and pickaxe
- this guide itself recommends using one space after the leading `#`
Merge pull request #337 from bruno-/fix_commented_output

Update a couple inconsistent commented outputs
Merge branch 'master' of https://github.com/bbatsov/ruby-style-guide
Started Classes and Modules.