Author: Marina Glancy
MDL-38596 Added caching to the list of course contacts
http://git.moodle.org/gw?p=moodle.git;a=commit;h=36ba8fded0f702d12788b8d2856fe63db20307c2
http://github.com/moodle/moodle/commit/36ba8fded0f702d12788b8d2856fe63db20307c2
+ 2.5 en [cachedef_coursecontacts,core_cache]