Removed the ResponsesController#sort_questions_by_order_number method.

We can call the sort method directly from the decorator.
Add Question#sorted_answers_for_response.
Add RadioQuestion#sorted_answers_for_response.
Add DropdownQuestion#sorted_answers_for_response & MultiChoiceQuestion#sorted_answers_for_response.
Added Category#sorted_answers_for_response.
Added MultiRecordCategory#sorted_answers_for_response.