Git commits in Moodle 2.8.x by Brendan Heywood

commit be72c3df676c01919195f9f6ff1eaaf149812eff
Author: Brendan Heywood <brendan@catalyst-au.net>
Date:   Thu, 02 Apr 2015 14:41:48 +0800
Tag:    v2.8.6

MDL-49740 Lock: Fixed task lock release bugs