Git commits in Moodle 3.1.6 by Arnaud Trouve

commit afbb1b7fb5fcb7a44b301ca175c5488b14291688
Author: Arnaud Trouve <ak4t0sh@free.fr>
Date:   Fri, 17 Mar 2017 15:29:49 +0800
Tag:    v3.1.6

MDL-58257 course: fix search containing a hyphen