Three new features, and a bug fix in a pear tree

Core fix for inconsistent list object for station preferences
Added stationdefaults preference (apply default settings to all stations)
Added stationfolder preference (generate stations automagically from a folder structure)
Added stationconfig preference (load other preference files as stations)
Moved get_conf_dict to utils.py
Added documentation for the stationdefaults preference
Added documentation for the stationfolder and stationconfig preferences (deefuzzer_doc.xml only)