offset_bars and regions

[Matt Flax <flatmax mimosaacoustics com>]

I have now implemented the regions plot as well. The source code is 
attached ... it has source code for the new regions plot, the new 
offset_bars plot, the new xyyc graph and the removal of the redundant 
variable from the original xyc graph.
I have also attached the image of the basics2 example which includes the 
offset_bars and regions in magenta.
The regions plot uses polygons to achieve solid plots. The offset_bars 
uses segments to plot each offset bar.
Matt

Attachment: basics2.jpg
Description: JPEG image

Attachment: gtkdatabox.flatmax.20120228.tar.bz2
Description: application/bzip