ListView sort_order ignored

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Create a new gui.ListView with sort_order='descending'
2. Add items to the list
3. Run your code

What is the expected output? What do you see instead?
The selected sort_column should list items in descending order. Instead the 
list remains sorted in ascending order.

What version of the product are you using? On what operating system?
Latest version of gui2py from github. wxPython3.0-win32-py27.

Original issue reported on code.google.com by rob.cro...@gmail.com on 15 Sep 2014 at 7:24