https://github.com/wiki-ai/wikilabels/issues/142

1. Use standard db naming

E.g. enwiki is en.wikipedia.org, ptwikibooks is pt.wikibooks.org, etc.

2. Allow for exceptions

• metawiki --> meta.wikimedia.org
• wikidatawiki --> wikidata.org
• mediawikiwiki --> mediawiki.org
• commonswiki --> commons.wikimedia.org
• specieswiki --> species.wikimedia.org
• etc.