* some changes

* moved some admin html code from php to twig templates (.html files)
* minimum PHP version required by installer is now 5.1.2, cause of spl_autoload_register functon.
* depracated Twig to version 1.20.0 cause of Autoloader
* removed unused admin stylish template

system/libs/twig/FunctionInterface.php

@@ -0,0 +1,40 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2010 Fabien Potencier
+ * (c) 2010 Arnaud Le Blanc
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Represents a template function.
+ *
+ * Use Twig_SimpleFunction instead.
+ *
+ * @author Arnaud Le Blanc <arnaud.lb@gmail.com>
+ *
+ * @deprecated since 1.12 (to be removed in 2.0)
+ */
+interface Twig_FunctionInterface
+{
+    /**
+     * Compiles a function.
+     *
+     * @return string The PHP code for the function
+     */
+    public function compile();
+
+    public function needsEnvironment();
+
+    public function needsContext();
+
+    public function getSafe(Twig_Node $filterArgs);
+
+    public function setArguments($arguments);
+
+    public function getArguments();
+}