Author: Tim Hunt
MDL-20636 listpreupgrade done.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=5ab62d9d3d464654f05d95054629f6cf68dce503
http://github.com/moodle/moodle/commit/5ab62d9d3d464654f05d95054629f6cf68dce503
+ 2.1 en [listpreupgradeintro,local_qeupgradehelper]