Author: Sam Hemelryk
MDL-25290 cache_session: Added default session cache store
http://git.moodle.org/gw?p=moodle.git;a=commit;h=d7f1f57391d4489683cda3244bfffbf8752c6310
http://github.com/moodle/moodle/commit/d7f1f57391d4489683cda3244bfffbf8752c6310
+ 2.4 en [pluginname,cache_session]