The terms `%d open|closed tickets` need to be made plural so that the terms
`open` and `closed` can be properly translated.

References:
(Crowdin login required)
http://i18n.osticket.com/translate/osticket-official/148/enus-de#3735

The software defines at least three contexts for the phrase "Open"

  * The name of a ticket queue (Open tickets)
  * A status of a ticket (Open / Closed)
  * An action to be performed (Open a ticket)

References:
(Crowdin login required)
http://i18n.osticket.com/translate/osticket-official/148/enus-de#2915

Also, the final version of the system will not require the `gettext`
extension for PHP

Use a PHP source file for the translation hash table rather than a
serialized version of the array. This will allow a PHP object cache such as
APC to cache the file and remove the overhead of parsing and unserializing
on each request.

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

User::fromVars in class ticket was the root. Eventually, in
DynamicForm::getDynamicFields(), isset($this->id) was used to detect
unsaved, new forms that have not been committed to the database; however,
the isset() method was not implemented for the ORM.

Some versions of PHP (5.3.6 on Windows at least) may corrupt `$ost` if it is
closed off as a global variable.

Fixes #917, #969

Starting with osTicket 1.8.1, users must receive an email and follow a link
in the email to get access to the ticket. With this new option, the email
verification step can be avoided in osTicket 1.9, because access is now only
granted to exactly one ticket.