adjust annotation vertical scroll to show currently selected/operated on annotation after a row-sort

Adjusting the annotation sort settings can dramatically rearrange the annotation rows, making a row which the user had been operating on disappear from the display. Ideally, after a sort, or some other operation (e.g. new annotation row appearing), the vertical scrolls should be automatically positioned to show the relevant annotation:
- if a new annotation row is added, the panel should scroll to show the new row
- if an annotation row has columns selected and the panel is reordered, then the scroll should change to where the annotation row is reordered to