Map "object" to "physical object" (#7663)

See comment 10:
https://issues.dp.la/issues/7663#note-10
Merge pull request #25 from dpla/7663-physical-object-mapping

Map "object" to "physical object" (#7663)
Fix UTC datestamp regression (fixes #7699)
Merge pull request #24 from dpla/7699-fix-datestamp-generator

Fix UTC datestamp regression (fixes #7699)
Initial stab at SCDL single profile
Add comments and simplify logic