Author: Sam Hemelryk
MDL-36120 cachestore_file: improved file storage method + new setting
http://git.moodle.org/gw?p=moodle.git;a=commit;h=08aaa637fb1873ee7f75212f6e41936bd7853838
http://github.com/moodle/moodle/commit/08aaa637fb1873ee7f75212f6e41936bd7853838
+ 2.4 en [singledirectory,cachestore_file]
+ 2.4 en [singledirectory_help,cachestore_file]