Upgrade Express to 4.4.1

Want strong ETags.

See https://github.com/visionmedia/express/wiki/Migrating-from-3.x-to-4.x

Connect is no longer part of Express, so middleware is no longer on the
`express` object. Instead, we import the things (occasionally with new
names) and use those.
Move-dvsa-user-satisfaction-modules

Move user satisfaction modules for book and change practical driving test dashboards
Re-jig visible user stages in line with service manager request for change booking dashboard
Merge pull request #562 from alphagov/Move-dvsa-user-satisfaction-modules

Move-dvsa-user-satisfaction-modules
Merge pull request #559 from alphagov/upgrade-express

Upgrade Express to 4.4.1
Remove improvement message from detailed dashboard

We're already working with these services, so it makes no sense to
encourage them to contact us.
Add draft 'Register to vote' dashboard
Remove capitals from lasting power of attorney

It's not capitalised on the service:

https://lastingpowerofattorney.service.gov.uk/
Add first 3 modules to 'Register to vote'

- Live service usage
- User satisfaction
- Service availability