Experiments with single-quotes break "Use This" functionality

If any experiment name contains a single quote, the lack of escaping in the dashboard causes a misnamed experiment (e.g. "You'll Love It" becomes "You") to be declared the winner, leaving all experiments looking like Losers and associated ab_test getting back a name it wasn't expecting.

(Escape mechanism is taken from http://www.sinatrarb.com/faq.html#escape_html)