Integrate somehow some parts of Europeana in the EOKG

[rtroncy]

We need to work on the relationship between Europeana content and EOKG in both ways:

1. Importing Europeana content in the EOKG with useful metadata. The first stop shop is the APIs that Europeana is providing, https://pro.europeana.eu/page/apis ... but we need guidance from the Historians to know what content is interesting to pull from / cc @Ileemans @williamtullett
2. Share the EOKG data in Europeana. The guide is available at https://pro.europeana.eu/share-your-data/process. Ideally, we would try to get funding to become and develop a Europeana aggregator