Git commits in Moodle 2.3.x by Troy Lee

commit 4126c81e32d9b381a5af9087ccf1870c19ae8695
Author: Troy Lee <troy.lee2008@gmail.com>
Date:   Thu, 09 May 2013 10:13:46 +0800
Tag:    v2.3.8

MDL-36020 overview/report: fix quiz regrade session lock