Author: M Kassaei
MDL-40992 quiz: let students to redo questions within an attempt
http://git.moodle.org/gw?p=moodle.git;a=commit;h=1700bd4dea94e151d07eb8dc47f9ad73dcd11413
http://github.com/moodle/moodle/commit/1700bd4dea94e151d07eb8dc47f9ad73dcd11413
+ 2.9 en [restartquestion,core_question]
+ 2.9 en [configrestartgradedquestions,mod_quiz]
+ 2.9 en [restartgradedquestions,mod_quiz]
+ 2.9 en [restartgradedquestions_help,mod_quiz]