Author: Sam Hemelryk
MDL-38343 cache: better test server strings
http://git.moodle.org/gw?p=moodle.git;a=commit;h=46c6c237d21b03745c180a37a1b58716f88364e0
http://github.com/moodle/moodle/commit/46c6c237d21b03745c180a37a1b58716f88364e0
+ 2.7 en [testservers_desc,cachestore_memcache]
+ 2.7 en [testservers_desc,cachestore_memcached]
+ 2.7 en [testserver_desc,cachestore_mongodb]