Follow the cursor without dragging

[KreerC]

I would like to suggest an improvement that could benefit my daily workflow: Following the cursor without needing to drag. This should be configurable of course, but I often find myself just quickly wanting to zoom in on an element and getting a quick overview of what I am dealing with. It should be combined with what I have already wished for in #116 for maximum efficiency.

In traditional magnification software, a lot of interaction happens by mouse because it is very intuitive for the type of problem, not necessarily because of efficiency.