Enable loading data sets from files for custom tasks (#1083)
* enable use of data files for custom tasks
* addressing PR comments, create new doc file, update docstring with types
* Update docs/source/offline-evaluation.md
Co-authored-by: Nathan Habib <30601243+NathanHB@users.noreply.github.com>
* add new doc to toctree
* Add offline evaluation section to documentation
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Co-authored-by: David Biagioni <dbiagioni@proofpoint.com>
Co-authored-by: Nathan Habib <30601243+NathanHB@users.noreply.github.com>
Co-authored-by: Dave Biagioni <7086434+davebiagioni@users.noreply.github.com>
