Author: Simey Lameze
MDL-26401 group: change import to use csv_import_reader class
http://git.moodle.org/gw?p=moodle.git;a=commit;h=d4d744d5448b1afa8d600d7f155981939b0a98da
http://github.com/moodle/moodle/commit/d4d744d5448b1afa8d600d7f155981939b0a98da
+ 3.8 en [csvfileerror,core_error]
+ 3.8 en [csvnodata,core_error]