MDL-43089, adding random question poup
MDL-43089, Adding quizquestionbank popup
MDL-43089, deleting irrelevant unittest in repaginate
Initial fix of question bank dialogue scrolling.

Thanks to Andrew Nichols for his help with this.
MDL-43089 deleting mod/quiz/questionbank.php
MDL-43089, tidying up
MDL-43089, added more unittest to repaginate
MDL-43089, add new question to the right place
comment out Call question bank
Reorder slots and pages correctly when dragged