Feature/add docs (#689)

* Add converted docs repo

* Set theme jekyll-theme-minimal

* Removed BC docs, added TOC

* Added TOCs, rewrote most important links in documentation. Linked README to new Github Pages site

* some link fixes

docs/programmers/api-functions/api-add-plugins-dir.md

@@ -0,0 +1,42 @@
+addPluginsDir()
+
+add a directory to the list of directories where plugins are stored
+
+Description
+===========
+
+Smarty
+
+addPluginsDir
+
+string\|array
+
+plugins\_dir
+
+
+    <?php
+
+    // add directory where plugins are stored
+    $smarty->addPluginsDir('./plugins_1');
+
+    // add multiple directories where plugins are stored
+    $smarty->setPluginsDir(array(
+        './plugins_2',
+        './plugins_3',
+    ));
+
+    // view the plugins dir chain
+    var_dump($smarty->getPluginsDir());
+
+    // chaining of method calls
+    $smarty->setPluginsDir('./plugins')
+           ->addPluginsDir('./plugins_1')
+           ->addPluginsDir('./plugins_2');
+
+    ?>
+
+       
+
+See also [`getPluginsDir()`](#api.get.plugins.dir),
+[`setPluginsDir()`](#api.set.plugins.dir) and
+[`$plugins_dir`](#variable.plugins.dir).