Do not automatically add Comment is Free tag as kicker

It's apparently a 'blog' tag.

Turns this

![screen shot 2014-11-24 at 17 36 14](https://cloud.githubusercontent.com/assets/1001642/5169580/854b9116-7400-11e4-854a-37a25e9dfed0.png)

into this

![screen shot 2014-11-24 at 17 36 21](https://cloud.githubusercontent.com/assets/1001642/5169581/898055be-7400-11e4-8beb-3c979b6653ec.png)