add imprint as flatpage

- add flatpages app to gnuviechadmin.settings.base.DJANGO_APPS
- add imprint handling to gnuviechadmin.context_processors.navigation, remove
  unused about page handling
- add URL 'imprint' to gnuviechadmin.urls
- replace link 'about' in template base.html with 'imprint'
- add templates for flatpages
- add german translation for imprint and contact navigation links

gnuviechadmin/gnuviechadmin/context_processors.py

@@ -34,8 +34,6 @@ def navigation(request):
         viewmodule = viewfunc.__module__
         if viewmodule == 'contact.views':
             context['active_item'] = 'contact'
-        elif viewmodule == 'about.views':
-            context['active_item'] = 'about'
         elif viewmodule in (
             'hostingpackages.views', 'osusers.views', 'userdbs.views',
             'managemails.views', 'websites.views', 'domains.views',
@@ -45,6 +43,11 @@ def navigation(request):
             'allauth.account.views', 'allauth.socialaccount.views'
         ):
             context['active_item'] = 'account'
+        elif (
+            viewmodule == 'django.contrib.flatpages.views' and
+            request.path.endswith('/impressum/')
+        ):
+            context['active_item'] = 'imprint'
         else:
             _LOGGER.debug(
                 'no special handling for view %s in module %s, fallback to '

gnuviechadmin/gnuviechadmin/settings/base.py

@@ -239,7 +239,9 @@ DJANGO_APPS = (
 
     # Admin panel and documentation:
     'django.contrib.admin',
-    # 'django.contrib.admindocs',
+
+    # Flatpages for about page
+    'django.contrib.flatpages',
 
     'crispy_forms',
 )

gnuviechadmin/gnuviechadmin/urls.py

@@ -18,6 +18,10 @@ urlpatterns = patterns(
     url(r'^osuser/', include('osusers.urls')),
     url(r'^admin/', include(admin.site.urls)),
 )
+urlpatterns += patterns(
+    'django.contrib.flatpages.views',
+    url(r'^impressum/$', 'flatpage', {'url': '/impressum/'}, name='imprint'),
+)
 
 # Uncomment the next line to serve media files in dev.
 # urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)