generate documentation from config.sample.php

admin_manual/configuration_server/config_sample_php_parameters.rst

@@ -1314,11 +1314,12 @@ for more information.
 	'redis.cluster' => [
 		'seeds' => [ // provide some/all of the cluster servers to bootstrap discovery, port required
 			'localhost:7000',
-			'localhost:7001'
+			'localhost:7001',
 		],
 		'timeout' => 0.0,
 		'read_timeout' => 0.0,
-		'failover_mode' => \RedisCluster::FAILOVER_ERROR
+		'failover_mode' => \RedisCluster::FAILOVER_ERROR,
+		'password' => '', // Optional, if not defined no password will be used.
 	],
 
 Connection details for a Redis Cluster
@@ -1342,6 +1343,9 @@ which then causes a FileLocked exception.
 
 See https://redis.io/topics/cluster-spec for details about the Redis cluster
 
+Authentication works with phpredis version 4.2.1+. See
+https://github.com/phpredis/phpredis/commit/c5994f2a42b8a348af92d3acb4edff1328ad8ce1
+
 ::
 
 	'memcached_servers' => array(