Git commits in Moodle 2.1.5 by David Penner

commit c3b0e64d811dd74dedd6c8c50855cf11ed0b37e0
Author: David Penner <contributor@tracker.moodle.org>
Date:   Wed, 18 Jan 2012 11:19:27 +0800
Tag:    v2.1.5

MDL-31160 block_navigation: Fixed incorrect thrid arg to substr.