Index a minimal (pid only) document if the document is prefiltered.
This avoids an server error when saving to solr.
Issue curationexperts/tufts-image-library#174

Code ported from:
https://github.com/TuftsUniversity/tuftsification-hydra/commit/ab4d5acf86991ee3e50414f4b171f156fd668fec
added valid pid checking
Add namespacing to fixtures task and use gem fixtures
removed devise version dependency, fixed a typo
Add additional testing fixtures
Add an appropriate solr prefix for TuftsFileMeta
Copied tests from MIRA
commit: https://github.com/curationexperts/mira/commit/3a891ad8808774581a6cf2f689cf3325a374dca4
Copy in test from mira
From commit:
https://github.com/curationexperts/mira/commit/3c52f6664ca9a9f684cea3e184e208b611914b90
Remove art & art history fixtures from test list