Add redis entrypoint and conf files

redis/docker-entrypoint.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+set -e
+
+# first arg is `-f` or `--some-option`
+# or first arg is `something.conf`
+if [ "${1#-}" != "$1" ] || [ "${1%.conf}" != "$1" ]; then
+	set -- redis-server "$@"
+fi
+
+# allow the container to be started with `--user`
+if [ "$1" = 'redis-server' -a "$(id -u)" = '0' ]; then
+	chown -R redis .
+	exec gosu redis "$0" "$@"
+fi
+
+exec "$@"

redis/redis.conf

@@ -0,0 +1,5 @@
+port 6379
+cluster-enabled yes
+cluster-config-file nodes.conf
+cluster-node-timeout 5000
+appendonly yes