Author: Sam Hemelryk
MDL-38343 cache: better test server strings
http://git.moodle.org/gw?p=moodle.git;a=commit;h=67ccf63800c1c2e6a8122f479589cc09ac5cd5d7
http://github.com/moodle/moodle/commit/67ccf63800c1c2e6a8122f479589cc09ac5cd5d7
+ 2.8 en [testservers_desc,cachestore_memcache]
+ 2.8 en [testservers_desc,cachestore_memcached]
+ 2.8 en [testserver_desc,cachestore_mongodb]