better understanding why station is removed in preprocessing

Add a more detailed error message why a station is removed inpreprocessing.py.

def f_proc(data_handler, station, name_affix, store, **kwargs):
    """
    Try to create a data handler for given arguments. If build fails, this station does not fulfil all requirements and
    therefore f_proc will return None as indication. On a successfull build, f_proc returns the built data handler and
    the station that was used. This function must be implemented globally to work together with multiprocessing.
    """
    try:
        res = data_handler.build(station, name_affix=name_affix, store_processed_data=store, **kwargs)
    except (AttributeError, EmptyQueryResult, KeyError, requests.ConnectionError, ValueError) as e:
        formatted_lines = traceback.format_exc().splitlines()
        logging.info(f"remove station {station} because it raised an error: {e} (from {' | '.join(formatted_lines[-3:])}")
        res = None
    return res, station