Changes to upper ontology accumulate

[saumier]

When the upper ontology is modified, both the new and old mapping remain.

Current behaviour: If you change the upper place name mapping, the old data from the previous mapping remains in the database and randomly display the old or new. In this example, the upper place was set to the country, and then changed to the administrative territory. See https://culture-intime-production.herokuapp.com/en/productions/show?uri=http://www.wikidata.org/entity/Q2945524&layout=2

Expected behaviour: If you change the upper place name mapping, the old mapping should be removed, and only the new remain.