Django-helpdesk

Fixes a few bugs, most notably in the login screen, but also a double translation bug

The first beta of the new 0.3.0 series!

Many many bugfixes and changes, but short story:

- Now supports Django 3 (meaning we now support only Python 3)
- Overhaul of user interface
- New features like merging tickets

As a beta release, do not use in important production! But we do appreciate if you can use it and give us feedback. Please file a new ticket with feedback, whether bugfixes or suggestions.

Updates some documentation, fixes some bugs in displaying knowledge base records, and fix some bugs with assigning tickets and sending mail.

This is very likely going to be the last release of the 0.2 series unless there's some super critical bug. Users are encouraged to try out the 0.3.0 beta and give us feedback for a real release before the end of the year.

Several helpful bugfixes:
- Fix issue with parsing email headers with comma in the name
- Closed ticket pagination
- Prevent tickets from depending on themselves
- Fix keyword query box in ticket list, bulk ticket handling buttons, javascript improvements
- Fix knowledgebase score handling error
- Documented previously undocumented HELPDESK_MAX_EMAIL_ATTACHMENT_SIZE setting
- Better default permissions for attachments
- French translation updates, fix bug in fixtures

This release shouldn't break anything as there was no new features added, so recommended for all users of the 0.2.x branch to upgrade ASAP.

Bugfix release
- Fill the follow-up field when authenticated (805)

Bugfix release
- fixes an NonType error (808)
- add pytz UTC configuration for testing (813)