Draft: 67 easy import ls

Created an easy procedure to import data, just by providing the dataframe to the import method. It works as follows:

• There is a new internal variable to the data object, col_import_name. If not specified, the name is taken as default value. The dimension of the DataObject is also taken into account, so if not enough names are provided, then the default name is taken an expanded.
• We use the same import_data method. However, now we can provide the dataframe data_import. If the callback is not None, this is taken as first option, and run, instead of using the data provided.
• Also valid for design_representation, but only when it can be captured in the dataframe. Hence, in principle, no images, etc.

This change has been tested on Semiramis already, and seems to work. Some more debugging might be necessary.