Git commits in Moodle 2.5.x by Francis Devine

commit 85251082bf373249eba3792653fee793e6146f07
Author: Francis Devine <francis@xeon.pw>
Date:   Wed, 04 Sep 2013 17:21:41 +0800
Tag:    v2.5.3

MDL-41417 course: prevent duplicate idnumbers being used when updating a course