Author: Andrew Nicols
MDL-66722 forum: Add gradeitem storage handler
Part of MDL-66074
http://git.moodle.org/gw?p=moodle.git;a=commit;h=f8da1b9353834b8178b545d2cfb53702240ff86c
http://github.com/moodle/moodle/commit/f8da1b9353834b8178b545d2cfb53702240ff86c
+ 3.8 en [error:notinrange,core_grading]