[dxwg] new commits pushed by davebrowning

The following commits were just pushed by davebrowning to https://github.com/w3c/dxwg:

* Update URLs to DataCite / DCAT-AP mapping

Just and editorial change, to point to the relevant specification, instead of its repository:
- Old URL: https://github.com/ec-jrc/datacite-to-dcat-ap/
- New URL: https://ec-jrc.github.io/datacite-to-dcat-ap/
  by Andrea Perego
https://github.com/w3c/dxwg/commit/f3761f63e02817de77fe8ba5541b28691e1b9a3b

* Merge pull request #337 from w3c/andrea-perego-patch-1

Update URLs to DataCite / DCAT-AP mapping
  by David Browning
https://github.com/w3c/dxwg/commit/0b97df6d147156d1f2d5693ba944fcbb6d0277df