feat: Rewrite of the core: avoid globals where possible

Create services for: login, status, router, database, AnonymousStatistics
Drop gesior.backward_support
Drop compat/pages.php
Drop part of compat/classes.php
Move signature to routes

system/pages/signature.php

@@ -0,0 +1,6 @@
+<?php
+defined('MYAAC') or die('Direct access not allowed!');
+
+chdir(TOOLS . 'signature');
+include TOOLS . 'signature/index.php';
+exit;