Merge branch 'fix/events-no-max-participants' into 'master'

Fix problem when event has no max participants limit

See merge request !557

website/events/api/serializers.py

@@ -116,7 +116,8 @@ class EventRetrieveSerializer(serializers.ModelSerializer):
         return unescape(strip_tags(instance.description))
 
     def _num_participants(self, instance):
-        if instance.num_participants() > instance.max_participants:
+        if (instance.max_participants and
+                instance.num_participants() > instance.max_participants):
             return instance.max_participants
         return instance.num_participants()