Git commits in Moodle 3.6.4 by Sara Cenni

commit 0a1a11aae4eadf21551ef06dc9d4dcdd6a077231
Author: Sara Cenni <sara.cenni@unibo.it>
Date:   Thu, 21 Mar 2019 23:23:39 +0800
Tag:    v3.6.4

MDL-64851 badge: reviewing badges of invisible courses