Merge branch 'patch-11' into 'dev-3.0'

Update index.php

See merge request !14

adminforce/index.php

 <?php
+if (!isset($_GET['content']) || empty ($_GET['content'])) $_GET['content'] = '/startseite';
+
     if (strpos ($_GET['content'], '/logout/') !== false) {
         session_start();
         unset($_SESSION['admin']);
@@ -11,7 +13,7 @@
 
 
 
-    if (!isset($_GET['content']) || empty ($_GET['content'])) $_GET['content'] = '/startseite';
+
     if (!file_exists('content' . $_GET['content'] . '.php')) $_GET['content'] = '/error/keine_seite';
 
     require ('../lib/extras.init.php');