Git commits in Moodle 2.4.6 by prateeksachan

commit bb6cacb9134dfa6e1da276f4cab706e557bb56fd
Author: prateeksachan <ps@prateeksachan.com>
Date:   Mon, 01 Jul 2013 16:59:10 +0800
Tag:    v2.4.6

MDL-40386: Fix for updating timemodified field in book_chapters