Add DwCA metadata tool

[beach53]

Edit by @grantfitzsimmons:

We need to have a tool to create the EML metadata that the export process currently requires.

https://ipt.gbif.org/manual/en/ipt/latest/gbif-metadata-profile

[grantfitzsimmons]

https://discourse.specifysoftware.org/t/dwca-data-exporting-in-specify-7/568

Still would be nice.