Contacts are added to the DataCite metadata

[ahmdthr]

Contacts are currently not added to the downloaded DataCite metadata because of this pycsw issue. A commit has already been merged to fix those, now waiting for a tagged alpha release from pycsw team so that we can update our dependency for pcysw.

This PR still works fine to download DataCita metadata, but won't include the contacts information. We only need to update pycsw version once we get a tagged release with this commit. After that we'll mark this PR as ready.

Checklist

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[ridoo]

depends on pycsw community to release new alpha version

[ahmdthr]

A PR on mapstore client is here that includes translations for German, French, Spanish and Italian.