draftable/scirate3 — pull request #260 by cgranade (2014-06-14 23:58:13+00:00)
Title: Twitter Summary Card support

I don't know Slim or Ruby well at all, so I'm not sure if this is useful yet, but I wanted to take a stab at enabling [Twitter Summary Cards](https://dev.twitter.com/docs/cards/types/summary-card) by adding a bit more metadata to the headers.