SPARQLgraph ingestion bug fix

Fixed a new and potentially serious bug in SPARQLgraph that caused the nodegroup json for import specs to be written improperly when there was a URILookup to a node whose name had been changed from the default.
This affects ingestion performed through SPARQLgraph using existing templates, as well as the creation of new import templates.

It does not affect python or service layer ingestion. It also does not affect ingestion performed in SPARQLgraph by dragging the nodegroup into the mapping tab (instead of the "normal" query tab).