Parameters
- link
 - a Link
 
This is called by AddLinkForData(Object,IDiagramModel) and AddLinkForData(Object,Object,IDiagramModel). Adding a link will request a new automatic layout. If either of the link's nodes are not Visible, the link will also be made not Visible. 
The implementation of this method should not modify the model. This method cannot and should not prevent or alter the addition of the link to the diagram.