changed all request to the new isset function

admin/login.php

@@ -25,7 +25,7 @@ if (isset($_POST["username"]) && isset($_POST["password"])) {
     die();
 }*/
 
-if (!($fs->getSessionData("login") == null) && ($fs->getSessionData("login") == "true-as-hell")) {
+if ($fs->issetSessionData("login") && ($fs->getSessionData("login") == "true-as-hell")) {
     header("Location: index.php");
     die();
 }