Fix breadcrumbs in translation project news
Add support for sending HTML-formatted email messages
Move NoticeForm factory to forms.py in pootle_notifications app
Add support for using markup in news forms

But keeping support for creating news items using HTML even if in settings
MARKUP_FILTER is set because in pootle_autonotices/signals.py the news items
are created using only HTML.
Email news using HTML version
Use the HTML version of the news items for RSS