Django-helpdesk

* `get_mail` bugfixes primarily on python3
* updated translations for zh_Hans (previously known as zh_CN)

Minor bugfix release for 0.2.x:

* Explicitly require django-bootstrap-form >= 3.3, which is required for Django 1.11

Initial release of 0.2.x branch. Includes following changes over 0.1.18:

* Updated Bootstrap CSS and jQuery interface, better theming
* Improved unit testing (infrastructure work for easier future development)
* Improved Python 3 support, particularly for email parsing of tickets/comments
* South database migrations are deprecated
* Requires Django 1.11.x, Python 2.7 or 3.4+
* Python 2 deprecated and will be removed in a future release

tagging 0.1.18 release