quiz 7.x-4.0-alpha2

Changes since 7.x-4.0-alpha1:

• Fixed #1314072: Auto revisioning system wasn't working. It created revisions only if a quiz hadn't been answered. It now does the opposite...
• Fixed: Notice: Undefined variable : data on quiz results page
• Fixed #1387712 reported by zeezhao: Undefined index notice on manage results page
• Fixed #1519744 reported by joel_liquidcms: Exception when adding question as user other than admin
• #1522290 reported by Bacteria Man: Added session data to the end action and hook_quiz_finished
• Fixed #1530040 by eternityempire: undefined index when submitting manage questions page
• fixed #1516424 reported by dkliewer: PDOexception when updating a quiz
• Fixed #1526400 reported by george.plescan: table prefixing problem
• Fixed #1515668 reported by eternityempire: Removed a notice on question creation form, and also made the cancel button work again, and removed the preview button.