Missing `visible` attribute to the `DenseNodeInfo`

[Yuri Astrakhan]

If a node is deleted, node's info object reports that, but dense node info does not. How can it be added?

I haven't dived too far into the spec, but it is a bit weird why the visible value is repeatable.

[Johannes Hofmann]

Thanks for catching this inconsistency!
It should be fixed by updating to the newest version (0.2.6) I just released.