Added a new base class called SupervisedTransformer from which supervised transformers inherit from. Before this, supervised transformers has a is_supervised property.
Added the possibility to configure how the progress is printed in model_selection.progressive_val_score. For instance, the progress can now be printed to a file by providing the file argument.
Added a stream.iter_sql utility method to work with SQLAlchemy.
The target_name parameter of stream.iter_csv has been renamed to target. It can now be passed a list of values in order to support multi-output scenarios.