Git commits in Moodle 2.6.6 by Michael Aherne

commit fba86dfd9806a21e2459972b7fdcd16cb7073cb9
Author: Michael Aherne <michael.aherne@strath.ac.uk>
Date:   Thu, 23 Oct 2014 19:05:31 +0800
Tag:    v2.6.6

MDL-47793 assign: Reset reveal identities