fixed infinite loop in inheritance (closes #66)

lib/Twig/Template.php

@@ -27,7 +27,7 @@ abstract class Twig_Template extends Twig_Resource implements Twig_TemplateInter
 
     protected function getParent($context, $parents)
     {
-        return call_user_func($parents[0], $context, array_slice($parents, 0));
+        return call_user_func($parents[0], $context, array_slice($parents, 1));
     }
 
     public function pushBlocks($blocks)

test/fixtures/tags/inheritance/multiple.test

@@ -0,0 +1,12 @@
+--TEST--
+"extends" tag
+--TEMPLATE--
+{% extends "layout.twig" %}{% block content %}{% parent %}index {% endblock %}
+--TEMPLATE(layout.twig)--
+{% extends "base.twig" %}{% block content %}{% parent %}layout {% endblock %}
+--TEMPLATE(base.twig)--
+{% block content %}base {% endblock %}
+--DATA--
+return array()
+--EXPECT--
+base layout index