adapt GO bot to use wikidata reference items when they exist

[Andrew Su]

Per an email from me on 2015-11-24 with subject "Wikidata for bacterial genome annotations" and subsequent emails through June 2016, we were planning to adjust our bots that add GO annotations to use wikidata reference items when they exist already. The goal is not to create/maintain a bibliobot.

Creating this ticket so we can prioritize it at some appropriate time in the future...

[Sebastian Burgstaller]

I will take care of this, I already built parts of the infrastructure required for this into the core library, recently.