Author: Jake Dallimore
MDL-67585 core: add course content item cache
To be indexed by userid_courseid.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=92715acd0cfe39c109cd75b7afacffe469c870fa
http://github.com/moodle/moodle/commit/92715acd0cfe39c109cd75b7afacffe469c870fa
+ 3.9 en [cachedef_user_course_content_items,core_cache]