Formatting fixes.
Added sections on controllers and require options.
Merge pull request #117 from objectpartners/feature/directive-controllers-require

Feature/directive controllers require
Added information about one root element in directive templates.
Merge pull request #118 from objectpartners/feature/directives-root-template

Added information about one root element in directive templates.
lab 4 adjusted and ready to go
Merge branch 'develop' into feature/lab-review

* develop:
  Added information about one root element in directive templates.
  Added sections on controllers and require options.
  Formatting fixes.