remove deskulu (unmaintained since 2016, unanswered issues, no active maintainers)

README.md

@@ -1470,7 +1470,6 @@ See https://staticsitegenerators.net and https://www.staticgen.com
 - [Bugzilla](https://www.bugzilla.org/) - General-purpose bugtracker and testing tool originally developed and used by the Mozilla project. `MPL-2.0` `Perl`
 - [Bumpy Booby](http://bumpy-booby.derivoile.fr/) - Simple, responsive and highly customizable PHP bug tracking system. ([Source Code](https://github.com/piero-la-lune/Bumpy-Booby)) `MIT` `PHP`
 - [Cerb](http://www.cerberusweb.com/) - Group-based e-mail management project. ([Source Code](https://github.com/wgm/cerb)) `DPL` `PHP`
-- [Deskulu](https://github.com/Taskulu/deskulu) - Opensource helpdesk and ticketing system based on Drupal 7. ([Demo](https://help.taskulu.com)) `GPL-2.0` `PHP`
 - [DiamanteDesk](http://diamantedesk.com/) - DiamanteDesk is FREE Open Source easy-to-use help-desk solution. ([Demo](http://diamantedesk.com/demo/), [Source Code](https://github.com/eltrino/diamantedesk-application)) `OSL-3.0` `PHP`
 - [django-todo](http://django-todo.org/) - django-todo is a pluggable, multi-user, multi-group, multi-list todo and ticketing system - a reusable app designed to be dropped into any existing Django project. ([Source Code](https://github.com/shacker/django-todo)) `BSD-3-Clause` `Python/Django`
 - [Flyspray](http://www.flyspray.org/) - Uncomplicated, web-based bug tracking system. ([Source Code](https://github.com/Flyspray/flyspray)) `GPL-2.0` `PHP`