Export coordinates from Wikidata

To allow to generate more lines efficiently, create an exporter from Wikidata.

Root problem:

Get the coordinates when the railway company doesn't publish a database without permission to reuse the data freely under sui generis database rights. For example, B-Rail and Infrabel don't publish such coordinates feed as open data.

Plan:

1. From a SPARQL query, create a csv with the Qid as external id and the correct coordinates.
2. Fill missing data or merge with another CSV