Git commits in Moodle 2.5.x by Roman Tsukanov

commit 1b5865168175e2148449f6c1fe58c7725e14e6ad
Author: Roman Tsukanov <tsukanovroman@gmail.com>
Date:   Mon, 25 Mar 2013 13:07:18 +0800
Tag:    v2.5.0-beta

MDL-38429: lesson report - Improve lesson statistics code.