Added method pyqp.columns.factory.column_instance_factory that creates new Column out of existing Column instance by calling 'duplicate' method; Refactored pyqp.columns.factory.default_column_factory to wort with list of column configurations
Added method pyqp.columns.factory.column_instance_factory that creates new Column out of existing Column instance by calling 'duplicate' method; Refactored pyqp.columns.factory.default_column_factory to wort with list of column configurations

michalbachowski/pyqp,michalbachowski/pyqp,michalbachowski/pyqp