Git commits in Moodle 2.7.x by Cameron Ball

commit 9f91c23536a31ba2dc91b0ba2ae726b1757a20cb
Author: Cameron Ball <cameron@moodle.com>
Date:   Thu, 11 Feb 2016 11:25:53 +0800
Tag:    v2.7.13

MDL-52651 htmlpurifier: Append rel=noreferrer to links.


commit a1168a7427f8fa1926a771fe8e6d10aeb6689686
Author: Cameron Ball <cameron@moodle.com>
Date:   Mon, 02 Nov 2015 15:09:26 +0800
Tag:    v2.7.11

MDL-51091 core_registration: session key check in registration.