In 5120, the reporting party also mentioned that they receive an error of
`script '/xxx/osTicket/kb/ajax.php' not found or unable to stat`.  This is
due to the AJAX call being inside the KB directory, and `/kb/ajax.php` truly
does not exist. This adds `ROOT_PATH` to the beginning of the AJAX call so
that no matter where it is, it will point to the correct location.

This updates all the old, outdated osTicket links in the software. This
includes things like the forum URL, the support URL, the Installation Guide
URL, etc.

This requires a hidden setting for the system language or the language
selection of the client (also currently hidden).

Multilanguage Support via gettext

- added gettext encapsulations to all texts i thought necessary
- added fallback function for the case that the gettext extension isn't loaded
- added browser language detection
- added gettext to the list of optional extensions in setup
- rewritten some of the texts to use sprintf instead of appending strings
- added german translation file
- removed mark_overdue-confirm from cannedresponses.inc.php

extend multi language support and a fex fixes

- Better detection of translation files
- Added functionality to redirect language codes (see redirecting
language codes)
- Ticket Status can be translated
- The Datepicker can be translated
- Extended functionality of 'testlang.php' to show what language code is
used to translate

Forgotten to apply a patch from RC5 to RC6

- Forgotten to change $var to $vars in line 380 of class.mailfetch.php
- Removed unneeded comment

Added php_gettext as primary translation engine

- Added php_gettext support (thanks to Danilo Segan and Steven
Armstrong)
- php_gettext is now the primary translation engine
- Extended language detection functionality

Add error/misconfiguration checks and fix undefined variables

This happens when upgrading from 1.6, the company information does not yet
exist (neither do the form tables)

Properly escape company name for display

Add overlay & loading spinner to client interface - shown on form submission to help cut down on double submits.