Icons in stock buttons (bug 78072)

["David Adam Bordoley" <bordoley msu edu>]

I just added a patch to bug 78072 that makes showing icons in stock buttons 
a style property. I'm not a great gtk hacker by any means so comments would 
be appreciated. Also I defaulted to including icons in buttons, but its 
worth noting that both windows and macos do not include icons in buttons so 
maybe the default should be changed. Is it possible to get this into gtk 2.4 
assuming the patch gets approved. 

dave