[Dunit-interest] Added 'select failed tests' button

[Morris, C. <ChrisM@SNELLINGCORP.COM>]

The latest GUITestRunner.* in CVS now has a 'select failed tests' button. 

I don't really like the button toolbar at the bottom of the screen --
doesn't seem ideal ... but it's easy to use and I don't really know what
would be better, so for the moment I added it there. 

Chris Morris
ch...@sn...