Git commits in Moodle 3.0.7 by Brendan Anderson

commit b6ed8fdf5f8fb5d5d0cbd36b059f678bac643466
Author: Brendan Anderson <brendan_anderson@hcpss.org>
Date:   Tue, 25 Oct 2016 03:22:13 +0800
Tag:    v3.0.7

MDL-54112 mod_assign: Add scale null grade filter