Generation framework uses set of edge/node files to build a UBKG mart

[AlanSimmons]

Request

It should be possible for the generation framework to use a set of edge/node files to build a UBKG mart--i.e., a UBKG context that combines the UBKG base context with the assertions from the edge/node files.

Use case

A user executes one of the paths queries in the ubkg-api and exports the response to a set of files in UBKG edge/node format. The files serve as ingest input for a UBKG mart.