Straight quote → unicode curly quotes filter

[r38y]

What do you think about including this filter?

https://gist.github.com/r38y/7663375

If this filter is applied and they want straight quotes, they can escape them with ". It will also turn -- into – and --- into —.

[jch]

I think it's a useful filter, but I'd like to hold off on including and supporting it in the main gem. If you do roll it into a standalone gem, I'd be happy to link to it from the README. 😉