Lots of refactoring and finally finished a working Question class.
 Also added a test class for Question.
Reduced the Question, Answer and Option classes to real templates (non-functional on their own) and added first working question model (SimpleInput, SimpleInputOption, SimpleInputAnswer).
Renamed class 'SimpleInput' to the (hopefully) more verbose 'SingleChoiceComment' (test class according).
Renamed class 'SingleChoiceComment' to (the hopefully even more verbose) 'SingleChoiceInput' (test class accordingly).
Also renamed the classes 'SimpleInputAnswer' and 'SimpleInputOption' to 'SingleChoiceInputAnswer' and 'SingleChoiceInputOption'.
Reworked the Unittest for class Question to test the template classes - somehow (using Dummy classes which add the minimal working code to the templates).