Added function filter

propositionController
Fixed QuestionGroup code
Merge remote-tracking branch 'origin/PouleRequestTesting' into dev
Added function filter

propositionController
Added a beforeFilter to get the QGroupID from the route
Fixed the MAR extension

Wrong folder. Whoops.
Merge remote-tracking branch 'origin/PouleRequestTesting' into dev
Added filterGetQuestion
Added page when proposition cannot be delete
Added specific classes for each question type
Added the STIPreloader functionnality. It will preload the classes specified in "StiPreloader.php" file