Author: Tim Hunt
MDL-20636 Clean up.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=14ed1aa2d85e5fcb72e6b9af77d1db8d9d052a34
http://github.com/moodle/moodle/commit/14ed1aa2d85e5fcb72e6b9af77d1db8d9d052a34
+ 2.1 en [deletedquestion,qtype_missingtype]
+ 2.1 en [deletedquestiontext,qtype_missingtype]