Populate Wikipedia interwiki ids for Commons and Wikidata

By default, "special" wikis are in the wikipedia family
when it comes to the interwiki table and interwiki ids.

e.g. [[:en:Berlin]] on Wikimedia Commons should resolve to
[[Berlin]] on English Wikipedia.

Change-Id: Ief5e6c9c3ae44e2eb157fd28e8c37db7c05f50e9
Merge "Populate Wikipedia interwiki ids for Commons and Wikidata"