Add changeable CMS_PERMISSION
Make specific fields on specific TicketTypes editable.
Validation and UI for editable fields
I18n for editable fields.
Add ability to send mails to a (sub)set of user through the website
Add admin links to second-level menu
Fix import side-effects
Merge branch 'develop' into fix/ticket106

Conflicts:
	pyconde/locale/de/LC_MESSAGES/django.po
Merge branch 'develop' into feature/mail
Externalize helpdesk email as setting.
Add translations
Merge pull request #138 from EuroPython/feature/mail

Add ability to send mails to a (sub)set of user through the website
Fixes #140 -- Allow buyers to assign tickets to themselves
Add another user set for emailing
Fixes #139 -- Automatically mark invoices with 0 EUR as 'payment_received'
Merge pull request #31 from EuroPython/feature/cms-permission

Add changeable CMS_PERMISSION
Fix error after logout if cms_permission are active

Solved in django-cms 3, but this is a beta :-/

https://sentry.markusholtermann.eu/europython/staging/group/66/