Quantity kind mapping to wikidata is wrong sometimes #24
Description
The mapping is done against the symbol of the entity instead of the quantity kind being mapped to. For example: https://rdfexplorer.mint.isi.edu/page/okn/i/mint/u_M_kilo_gram_kg
The quantity kind is "kg" in wikidata, but "gram" should be the correct one. Should add a "wikidata unit" relationship to indicate the equivalent in Wikidata. owl:sameAs may not always be correct.