Fix for Python 3.

pelicanconf.py

-#!/usr/bin/env python
-# -*- coding: utf-8 -*- #
-from __future__ import unicode_literals
-
 AUTHOR = u'Dominik George'
 SITENAME = u'Dominik George'
 SITESUBTITLE = u'Free Software Fellow, Education Enthusiast, sozialliberal'

publishconf.py

-#!/usr/bin/env python
-# -*- coding: utf-8 -*- #
-from __future__ import unicode_literals
-
 # This file is only used if you use `make publish` or
 # explicitly specify it as your config file.
 
@@ -14,7 +10,7 @@ SITEURL = 'https://www.dominik-george.de'
 RELATIVE_URLS = True
 
 FEED_ALL_ATOM = 'feeds/all.atom.xml'
-CATEGORY_FEED_ATOM = 'feeds/%s.atom.xml'
+#CATEGORY_FEED_ATOM = 'feeds/{slug}.atom.xml'
 
 DELETE_OUTPUT_DIRECTORY = True