Plot stacked areas and confidence bands as filled polygons, or add polygons to existing plots. A variety of input formats are supported, including vectors, matrices, data frames, formulas, etc.
o Improved areaplot(legend=...) example.
o Added function confplot() to plot confidence bands.
o Added arguments 'legend' and 'args.legend' to areaplot() to draw a legend.
o Initial release, providing the function areaplot().