Git commits in Moodle 2.8.4 by Vadim Dvorovenko

commit d3f49a8c84f84d4d43b3d3e5a53f5adc6d2a6e4a
Author: Vadim Dvorovenko <Vadimon@mail.ru>
Date:   Fri, 23 Jan 2015 10:49:46 +0800
Tag:    v2.8.4

MDL-48955 filter_mathjax: Regexp fix for texfiltercompatibility mode