Update oojs.json

* Repo moved to @wikimedia
  per https://github.com/trevorparscal/oojs (now a fork of wikimedia/oojs)
* Title is OOjs instead of OOJS
  per https://github.com/wikimedia/oojs/commit/82d5405480d066cb3d5460be0f7befc9f8dfa0d1
Merge pull request #406 from Krinkle/oojs

Update oojs.json