Duplicate structure in a different viewer


Contrary to the screenshot, the `Duplicate In` option is not listed in a Neuron on the left sidebar, but when the user selects a Viewer.

This should be implemented as a redux action and the reducer will create or update a widget state so that this widget contains the same data and related configuration as the source viewer.

Part of this ticket:

* Implement Popup Menu logic to select active viewer or new viewer
* Implement Duplicate In Redux action and Reducer

The state change will be handled by the LayoutManager in case of a new widget or by the widget itself if it was updated. This is not part of this ticket.