Use Upstream Memcached Image

This commit changes the default Memcached Image to the Upstream:
 * https://hub.docker.com/_/memcached/

Author: intlabs

memcached/values.yaml

@@ -4,7 +4,7 @@
 # name: value
 
 images:
-  memcached: quay.io/stackanetes/stackanetes-memcached:newton
+  memcached: docker.io/memcached:latest
   pull_policy: "IfNotPresent"
 
 upgrades: