Author: Stephen Bourget
MDL-48883 Lesson: Add question viewed and answered events
http://git.moodle.org/gw?p=moodle.git;a=commit;h=8101328a6993d9a0dcf76c15f81f21fdf112d3ae
http://github.com/moodle/moodle/commit/8101328a6993d9a0dcf76c15f81f21fdf112d3ae
+ 2.9 en [eventquestionanswered,mod_lesson]
+ 2.9 en [eventquestionviewed,mod_lesson]