[xdot] Graph.get_jump() accuracy improvement proposition

```
Currently the method finds the first edge that fits into some radius around
the mouse pointer and often selects an edge that is farther than others -
just because it was found first.

Another more useful approach would be to find the closest edge. I can
provide some demo code for this if you like.
```

Original issue reported on code.google.com by `Alexey.K...@gmail.com` on 17 Jun 2009 at 6:51
