Author: Tim Hunt
MDL-48008 gradeimport_xml: report errors usefully
http://git.moodle.org/gw?p=moodle.git;a=commit;h=913919527368828c2a99752760403d02d3246ed2
http://github.com/moodle/moodle/commit/913919527368828c2a99752760403d02d3246ed2
+ 2.6 en [errorduringimport,gradeimport_xml]