Fix an infinite recursion loop when calling Predis\Client::multiExec() (ISSUE #14).

lib/Predis.php

@@ -266,7 +266,7 @@ class Client {
     }
 
     public function multiExec(/* arguments */) {
-        return $this->sharedInitializer(func_get_args(), 'multiExec');
+        return $this->sharedInitializer(func_get_args(), 'initMultiExec');
     }
 
     private function initMultiExec(Array $options = null, $transBlock = null) {