Author: sam marshall
MDL-39448 MUC: Memcache configurable key names
http://git.moodle.org/gw?p=moodle.git;a=commit;h=1df3b0ae2441d46d58169635af14881d4b65008a
http://github.com/moodle/moodle/commit/1df3b0ae2441d46d58169635af14881d4b65008a
+ 2.4 en [prefix,cachestore_memcache]
+ 2.4 en [prefix_help,cachestore_memcache]