Fix staré Django

mamweb/context_processors.py

@@ -11,9 +11,9 @@ def vzhled(request):
     return {'noc' : noc}
 
 def april(req):
-    if 'X-April' in req.headers:
+    if 'HTTP_X_APRIL' in req.META:
         try:
-            year = int(req.headers['X-April'])
+            year = int(req.META['HTTP_X_APRIL'])
             return {'april': year}
         except:
             pass # Fall-back to regular behaviour