Avoiding grey background and relief when selecting button

[Lars Clausen <lc statsbiblioteket dk>]

Hi again!

I've cut down on the borders on the image-based toggle buttons in a
GtkList in Dias layer widget, but there's still some things that are not
good.  When the mouse moves over the button, there's still an up relief
drawn, and when the button is selected, there's a down relief.  Can
those be turned off?  

Additionally, the background becomes grey when selecting, but only
temporarily, then next time I select the list item it's painted like the
rest of the background.  I see I can set the selected background style
for the entire window, but can I set it for just the button?

I'd like to avoid Todd's idea of using an app-specific rc file, as that
seems to be fraught with installation dangers and too much overriding of
peoples styles.  I'm always afraid of stuff that'll add more complexity
to automake:)

-Lars