Delete Data Node
Data nodes can be deleted one by one or as batch.
Single delete
A single data node is deleted by clicking on the 
button, which appears on mouse-over to the left of the data node name in the List of Data Nodes.
Batch delete
Multiple data nodes can be deleted together by selecting them and then clicking the 
button.
Data Node Dependencies
Should there be a reference to this node, TIS will block deletion and show a warning.
It is not possible to delete before references are removed.
