Git commits in Moodle 3.3.x by Thinh Pham

commit c0f75375fe52ab0644901007098f910aea2cf637
Author: Thinh Pham <thinh.phamtien@nashtechglobal.com>
Date:   Thu, 28 Sep 2017 17:01:13 +0800
Tag:    v3.3.4

MDL-60079 User tours: leave unnecessary aria tags in the page