Git commits in Moodle 2.3.0 by Eduardo Pinto

commit dd30ae41d079aa61dd71225497c44f9ed1c2b999
Author: Eduardo Pinto <efgpinto@gmail.com>
Date:   Thu, 23 Feb 2012 14:10:18 +0800
Tag:    v2.3.0-beta

MDL-26496 Lesson Module: removed warning when no answer is selected from single choice question