Dear VXL Maintainers,

I am thinking of changing the zoom action on vgui_viewer2D_tableau. It is more convenient, especially for large images, to zoom around the point that is clicked. So for example, if one clicks CNTL_LEFT near the edge of the viewport, the image will zoom in and scroll so that the clicked point is at the center of the viewport.  Unless I hear negative comments, I will make the change in a few days.