Git commits in Moodle 2.9.0 by Huy Hoang

commit 1d693611e51a408800fa681f8e01f3571a27d341
Author: Huy Hoang <hoang027@umn.edu>
Date:   Mon, 10 Nov 2014 12:14:31 +0800
Tag:    v2.9.0-beta

MDL-39692 grade: Ability to delete letter boundary