Git commits in Moodle 3.4.0 by Mathieu Petit-Clair

commit c14e697ee6f226422232f7b6e19e6118f265098f
Author: Mathieu Petit-Clair <mathieu@petitclair.ca>
Date:   Tue, 16 May 2017 15:00:51 +0800
Tag:    v3.4.0-beta

MDL-58952 admin: use valid default for language selection dropdown.