Add light weight CMS system to manage pages

[mgvd]

There is no way to handle custom pages with VOKO specific content. To avoid adding that content (like privacy statement already is) to the repo, there should be some kind of CMS system, to add pages, and edit the content on that pages.

Wagtail or django-cms seem overly heavy. Maybe just a page model, with a rich text field can suffice for now.

[MichelJansen91]

This would be great for my VOKO Amersfoort fork as well. Right now it is hard to contribute to the Utrecht repository, since I need to change a lot of content files before I can use it for our own deployment. Continuously rebasing is unfortunately not realistic, and basically impossible to automate. I would really like to help with this issue as well.