Git commits in Moodle 3.4.3 by Nick Phillips

commit 173b5ea5ac5818f4a1cf77d0472f40556bc8b83a
Author: Nick Phillips <nick.phillips@otago.ac.nz>
Date:   Mon, 15 May 2017 07:55:49 +0800
Tag:    v3.4.3

MDL-55532 gradebook: fix grade export to include category names