button widget.  I also added 4 new button styles that correspond to
the 4 types of arrow button.  Lastly, I had to move some things around
so that is why there seem to be a lot of code changes in this commit.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%402585