updating README.md to include the new eviction strategy
updating README.md to include the new eviction strategy

twitter/twemcache,twitter/twemcache,rajeshaavuty/twemcache_vbox_src,tempbottle/twemcache,rajeshaavuty/twemcache_vbox_src,tempbottle/twemcache,tempbottle/twemcache,twitter/twemcache,tempbottle/twemcache,twitter/twemcache,rajeshaavuty/twemcache_vbox_src,rajeshaavuty/twemcache_vbox_src