[proSilver] viewtopic_body.html: Change 'back2top' anchor in to '#top'

In proSilver's viewtopic_body.html every post contains a small arrow that sends the user back to the top of the page (class "back2top"). This arrow links the user to anchor #wrap . However, proSilver has a well-placed anchor conveniently named #top for exact this purpose in its overall_header.html. I believe the anchor should be changed from #wrap to #top.