Comment cancel

# Open: Discussion

When writing a comment, I would like an easier way than holding backspace to clear my comment.
User, meet the cancel button.

## Looky
![cancel-comment](https://f.cloud.github.com/assets/31692/1887469/02a34ba2-79fe-11e3-94f6-4de7b3c590bc.png)

![ABORT!](http://stream1.gifsoup.com/view2/3604847/abort-o.gif)