Author: Andrew Nicols
MDL-59890 calendar: Add ability to add category events
http://git.moodle.org/gw?p=moodle.git;a=commit;h=05f184bb7f8074f9dc87b3c7520d6ccfaf86753d
http://github.com/moodle/moodle/commit/05f184bb7f8074f9dc87b3c7520d6ccfaf86753d
+ 3.4 en [categoryevents,core_calendar]
+ 3.4 en [eventtypecategory,core_calendar]
+ 3.4 en [typecategory,core_calendar]