Author: Jason Fowler
MDL-44754 Atto: Explaining what group names are used for in toolbars
http://git.moodle.org/gw?p=moodle.git;a=commit;h=87c0e4e06baab7592cac5f66592ed66378e4b91c
http://github.com/moodle/moodle/commit/87c0e4e06baab7592cac5f66592ed66378e4b91c
+ 2.7 en [toolbarconfig_desc,editor_atto]