Git commits in Moodle 3.3.1 by Skylar Kelty

commit 761ac5a0aa51a3b41eea344fcb24a109770e2080
Author: Skylar Kelty <s.kelty@kent.ac.uk>
Date:   Thu, 20 Apr 2017 18:14:46 +0800
Tag:    v3.3.1

MDL-58658 caching: Add static acceleration unit test for empty arrays

commit 32ec2da15106dab8f342058c635dc758aa603cad
Author: Skylar Kelty <S.Kelty@kent.ac.uk>
Date:   Thu, 20 Apr 2017 16:49:09 +0800
Tag:    v3.3.1

MDL-58658 caching: Fix static acceleration for empty arrays