add PlotPanel.get_config() method to get configuration (theme settings, sizes, line trace settings) as a dictionary and PlotPanel.set_config() to set using that dictionary as keyword/arguments. add "Save" and "Load" configuration to PlotFrame, using these dictionaries saved to/loaded from yaml files. some reordering of widget creation so that tab navigation of PlotConfigFrame works a bit more fluidly. add and tweak scope mode example avoid exceptions from get_suplotspec().get_position(fig) if there is no data, so that bounds are not yet reasonable.