Security fix: unauthorized access (#10091)

* Security fix: unauthorized access
Affects nginx users:
Moved php files outside of public html directory (Apache was protected by .htaccess)

Affects all users:
Some files did not check for authentication and could disclose some info.
Better checks before including files from user input

* git mv html/includes/ includes/html
git mv html/pages/ includes/html/

includes/html/reports/example.pdf.inc.php

@@ -0,0 +1,4 @@
+<?php
+
+$pdf->AddPage();
+$pdf->writeHTMLCell(0, 0, '', '', 'yeah', 0, 1, 0, true, '', true);