Author: Ryan Wyllie
MDL-54687 message: messaging widget styling
http://git.moodle.org/gw?p=moodle.git;a=commit;h=4d0fa50125c48ab9478400b78dd9d103e7f02b19
http://github.com/moodle/moodle/commit/4d0fa50125c48ab9478400b78dd9d103e7f02b19
+ 3.2 en [deletemessagesandconvos,core_message]
+ 3.2 en [selectmessagestodelete,core_message]
+ 3.2 en [writeamessage,core_message]