related to #1693 changed smarty version to 4.1.0

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

@@ -0,0 +1,32 @@
+setCacheDir()
+
+set the directory where the rendered template\'s output is stored
+
+Description
+===========
+
+Smarty
+
+setCacheDir
+
+string
+
+cache\_dir
+
+
+    <?php
+
+    // set directory where rendered template's output is stored
+    $smarty->setCacheDir('./cache');
+
+    // chaining of method calls
+    $smarty->setTemplateDir('./templates')
+           ->setCompileDir('./templates_c')
+           ->setCacheDir('./cache');
+
+    ?>
+
+       
+
+See also [`getCacheDir()`](#api.get.cache.dir) and
+[`$cache_dir`](#variable.cache.dir).