Author: Andrew Nicols
MDL-59890 calendar: Display category events on calendars
http://git.moodle.org/gw?p=moodle.git;a=commit;h=d0e56d847a13880b0cefcff995abe77222a4c8fe
http://github.com/moodle/moodle/commit/d0e56d847a13880b0cefcff995abe77222a4c8fe
+ 3.4 en [categoryevent,core_calendar]