related to #1693 changed smarty version to 4.1.0

include/smarty/docs/programmers/api-functions/api-set-plugins-dir.md

@@ -0,0 +1,46 @@
+setPluginsDir()
+
+set the directories where plugins are stored
+
+Description
+===========
+
+Smarty
+
+setPluginsDir
+
+string\|array
+
+plugins\_dir
+
+
+    <?php
+
+    // set a single directory where the plugins are stored
+    $smarty->setPluginsDir('./plugins');
+
+    // view the plugins dir chain
+    var_dump($smarty->getPluginsDir());
+
+    // set multiple directoríes where plugins are stored
+    $smarty->setPluginsDir(array(
+        './plugins',
+        './plugins_2',
+    ));
+
+    // view the plugins dir chain
+    var_dump($smarty->getPluginsDir());
+
+    // chaining of method calls
+    $smarty->setTemplateDir('./templates')
+           ->setPluginsDir('./plugins')
+           ->setCompileDir('./templates_c')
+           ->setCacheDir('./cache');
+
+    ?>
+
+       
+
+See also [`getPluginsDir()`](#api.get.plugins.dir),
+[`addPluginsDir()`](#api.add.plugins.dir) and
+[`$plugins_dir`](#variable.plugins.dir).