Escape HTML Entities

An error similar to this:

    UsersController# (NameError) "undefined local variable or method `foo' for #<UsersController:0x0000000d2f4c18>"

Is currently displaying like this, because the brackets around `<UsersController...>` are not being escaped.

<table><tr><th>Exception</th><td>undefined local variable or method `foo' for #<UsersController:0x0000000d2f4c18></td></tr><tr><th>Last Occurrence</th><td>February 14, 2013 11:54:30 -0800</td></tr><tr><th>Count</th><td>1</td></tr></table>

With this pull request, it will now display as:

<table><tr><th>Exception</th><td>undefined local variable or method `foo' for #&lt;UsersController:0x0000000d2f4c18&gt;</td></tr><tr><th>Last Occurrence</th><td>February 14, 2013 11:54:30 -0800</td></tr><tr><th>Count</th><td>1</td></tr></table>

I'm just using Ruby's basic built in `CGI.escapeHTML`