Hiho!

 This is a patch which will correct every shadow of the type
 GTK_SHADOW_ETCHED_IN and ....OUT. There were some pixel error.
 Further the vars thickness_light and ...dark have been killed
 because they were hardcoded to 1 and so the loops did nothing
 than waste cpu cpucylcles with the same wrong result...

 This patch applies properly against CVS branch and will
 compile without problems. The results have been approved with
 testgtk and xmag.

Servus,
       Daniel