Have an edge point to the centre of another edge #2938

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I assume this can be done by calling graph.updateItem and set the target to an {x, y} that is the center of the edge. The center of the edge can be calculated by having access to the target edge, which can be done at click events. However, I am not sure where I should do this to have access to both the graph, to call updateItem, as well as the target edge. When the edge is clicked, a event is fired in my app that adds this relation to the redux store. I think it should be done with afterDraw, but here I can't access graph.updateItem