Author: Petr Skoda
MDL-30929 detect incorrect major version upgrades
http://git.moodle.org/gw?p=moodle.git;a=commit;h=c12210514bc1ff62fc1ba3d5a245cf6ae3a3551f
http://github.com/moodle/moodle/commit/c12210514bc1ff62fc1ba3d5a245cf6ae3a3551f
+ 2.3 en [upgradestalefiles,core_admin]