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/graphs/wireless/errors.inc.php

@@ -0,0 +1,8 @@
+<?php
+
+$scale_min = '0';
+
+$unit_long = 'Errors (bps)';
+$unit = 'bps';
+
+include 'wireless-sensor.inc.php';