[PHP-WEBMASTER] [web-php] PR #1177: allow "/" when editing code

[soyuka]

Pull Request: https://github.com/php/web-php/pull/1177
Author: soyuka

It was reported that you can't hit "/" when editing code, this fixes it. I was 
suprised that this part of the code doesn't use `mousetrap` as in 
`js/common.js`.