Author: sam marshall
MDL-64454 Admin: Warning if cron does not run frequently
There is an existing warning if cron doesn't run at all (hasn't run
for 24 hours). This commit adds a warning if cron hasn't run for 3
minutes, based on the recommendation that cron should run every
minute.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=b18034ed67e640dbeb7e78907eca69d9611cc489
http://github.com/moodle/moodle/commit/b18034ed67e640dbeb7e78907eca69d9611cc489
+ 3.7 en [croninfrequent,core_admin]