show svg in error dialog

Don't show a continue button when we hit an error. Instead, pop our error dialog and show a copy of the svg.

![image](https://cloud.githubusercontent.com/assets/1767466/5036339/d0fdf3e0-6b33-11e4-8803-209057c37052.png)

Could be worth testing this cross-browser (though it looks like this helper should mitigate `cloneNode`'s issues)