Git commits in Moodle 3.1.5 by Eric Merrill

commit b7afb511328b09dd4bb2a647fac1052d91ca09af
Author: Eric Merrill <merrill@oakland.edu>
Date:   Mon, 10 Oct 2016 21:03:11 +0800
Tag:    v3.1.5

MDL-56592 gradereport_user: Add ability to view report as other user