Notification of string changes

Author: David Monllaó
MDL-64783 analytics: Activities due insight forwards to calendar
The patch includes changes applied after the peer review.


http://git.moodle.org/gw?p=moodle.git;a=commit;h=982fef46f43cfa8d77d990b4d794a149dc8a3908
http://github.com/moodle/moodle/commit/982fef46f43cfa8d77d990b4d794a149dc8a3908

- 3.7 en [gotodashboard,core]