Update Express from 3.4.0 to 3.4.7
Update Express from 3.4.0 to 3.4.7

https://github.com/visionmedia/express/compare/3.4.0...3.4.7

https://github.com/visionmedia/express/blob/3.4.7/History.md

This release includes lots of updates to Connect, the middleware Express
is based on. It also adds a res.vary() method to set the Vary header and
a load of other bugfixes.

keithiopia/spotlight,keithiopia/spotlight,alphagov/spotlight,keithiopia/spotlight,alphagov/spotlight,tijmenb/spotlight,alphagov/spotlight,tijmenb/spotlight,tijmenb/spotlight