Git commits in Moodle 3.7.0 by Kathrin Osswald

commit ee6484497bf681a5404f30dfb1657973536f1bbb
Author: Kathrin Osswald <kathrin.osswald@uni-ulm.de>
Date:   Fri, 27 Apr 2018 16:39:48 +0800
Tag:    v3.7.0-beta

MDL-62223 mod_assign: Improve submission statements