Cache modified to use drivers from drivers/cache, cache configuration added to installation

Similar to #951, modified for cache drivers in library/drivers/cache, removed unused constant DIR_DATABASE from config and added cache configuration to installation.
As suggested in comment on #951 I checked what danielkerr has done and this seemed to be missing. I do not know whether it was intentionally left out, but cache drivers were useless with cache class left as it was, and there was no option to change used driver apart from adding CACHE_DRIVER constant to config.php manually. 

PS.: If you find my request too messy again[or if there is anything wrong with it] I would appreciate if you were more specific in what is wrong so I can make it better next time. Thanks.