Author: Jean-Michel Vedrine
MDL-48715 mod_lesson: completion rules must not be dependent
http://git.moodle.org/gw?p=moodle.git;a=commit;h=4b570f714475bacc20d3cfab2ff25391ee07e5ba
http://github.com/moodle/moodle/commit/4b570f714475bacc20d3cfab2ff25391ee07e5ba
+ 2.9 en [completiontimespent,mod_lesson]