Release 4.74

• serpent 1.27 required to avoid regression in previous version
• fixed marshal serializer problem that prevented it to even call register() in the name server.
  Its dumpsCall is now able to use the class_to_dict conversion for unmarshallable types
  (in simple situations, not recursively). Previously, you would get a ValueError: unmarshallable object.
• msgpack, json and marshal serializers now understand how to serialize array.array the same way serpent already did