T&A: Refactor ilListOfQuestions according to data table component

[lukas-heinrich]

Refactors ilListOfQuestionsTable by using the DataTable component instead of ilTable2GUI inheritance. Removes unnecessary code and adjusts the unit tests:

• Creates a new Table class that implements the creation and formatting of columns and rows
• Replaces getter and setter with queries to the test object
• Removes legacy code that is always false
• Removes the template of the table rows