public MongoTransitionRepository(IDataTypeRegistry dataTypeRegistry, String connectionString, String collectionName = "transitions")
        {
            _dataTypeRegistry = dataTypeRegistry;
            _serializer = new MongoTransitionSerializer(dataTypeRegistry);
            _server = new MongoTransitionServer(connectionString, collectionName);

            EnsureIndexes();
        }
        public MongoTransitionRepository(IDataTypeRegistry dataTypeRegistry, String connectionString, String collectionName = "transitions")
        {
            _dataTypeRegistry = dataTypeRegistry;
            _serializer       = new MongoTransitionSerializer(dataTypeRegistry);
            _server           = new MongoTransitionServer(connectionString, collectionName);

            EnsureIndexes();
        }