Sb2 : UI : minor : "Next" finds current annotation

When the cursor is placed within an annotation, and the “Next” button is pressed within the “Find Annotation” dialogue box, the current annotation is highlight, rather than the next one. In my opinion, it should proceed to the next after the current annotation – and of course the “Previous” button should not select the current annotation either. It can already, in both cases, be presumed to have been found.

Done for beta 3.