Git commits in Moodle 3.7.1 by Kathrin Osswald

commit ec60f63f59eb5243a2a75f22bf184fd7e343b6e1
Author: Kathrin Osswald <kathrin.osswald@uni-ulm.de>
Date:   Thu, 23 May 2019 21:01:10 +0800
Tag:    v3.7.1

MDL-63240 theme Boost: Removed z-indexes for border styling in navdrawer