Author: yusufwib01
MDL-85777 message: Disable message input when sending isn’t allowed
http://git.moodle.org/gw?p=moodle.git;a=commit;h=bdd055b8ed820a342c8b9eb3d2ebeb5fd0000d76
http://github.com/moodle/moodle/commit/bdd055b8ed820a342c8b9eb3d2ebeb5fd0000d76
+ 5.1 en [cannotsendmessages,core_message]
+ 5.1 en [nopermissiontosend,core_message]