Create new pipeline to fetch dependency provenance data

ScanCode Toolkit identifies dependencies from package manifest files, but in most cases what you really want is the provenance data that can be retrieved from a package repository. The enhancement request is to build a new SCIO pipeline with at least one example of fetching the provenance data from a package rep to use as a template. In a common use case you may want to include fetching package repo provenance data for 2 or 3 package types.
This is related to:
- https://github.com/nexB/scancode-toolkit/issues/2591
- https://github.com/nexB/scancode.io/issues/579
- https://github.com/nexB/scancode.io/issues/228

I suspect that this enhancement may require Data Model changes.