Author: Andrew Nicols
MDL-66828 core: Add toast-style notifications
Part of MDL-66074
http://git.moodle.org/gw?p=moodle.git;a=commit;h=224ea04e68b7e9180da50dc2bd3dfc5eda6be38b
http://github.com/moodle/moodle/commit/224ea04e68b7e9180da50dc2bd3dfc5eda6be38b
+ 3.8 en [dismissnotification,core]