Git commits in Moodle 2.7.17 by Tim Hunt

commit 2045bc333ab31536071ffa3f76958cd52cb6fd1f
Author: Tim Hunt <T.J.Hunt@open.ac.uk>
Date:   Tue, 27 Sep 2016 02:46:22 +0800
Tag:    v2.7.17

MDL-53744 question file access: fix access checks