fixed open function phpdoc

Author: alexander-schranz

src/Redis.php

@@ -119,8 +119,10 @@ public function isConnected() {}
      * @param float     $timeout
      * @param null      $reserved
      * @param int       $retry_interval
+     * @param float     $read_timeout
+     * @return bool
      */
-    public function open( $host, $port = 6379, $timeout = 0.0, $reserved = null, $retry_interval = 0 ) {}
+    public function open( $host, $port = 6379, $timeout = 0.0, $reserved = null, $retry_interval = 0, $read_timeout = 0.0 ) {}
 
     /**
      * Connects to a Redis instance or reuse a connection already established with pconnect/popen.