Author: Shamim Rezaie
MDL-31355 mod_forum: different message when duedate has passed
http://git.moodle.org/gw?p=moodle.git;a=commit;h=82482e3d3e826d93feb8ffd95b2227544922a4ee
http://github.com/moodle/moodle/commit/82482e3d3e826d93feb8ffd95b2227544922a4ee
+ 3.7 en [thisforumisdue,mod_forum]