Author: David Ligne
MDL-56442 administration: Display hours in maintenance mode messages
http://git.moodle.org/gw?p=moodle.git;a=commit;h=f2510387e5a1945b5faff66629ccfdf384013d0c
http://github.com/moodle/moodle/commit/f2510387e5a1945b5faff66629ccfdf384013d0c
+ 3.2 en [maintenancemodeisscheduledlong,core_admin]