This commit moves user-related navigation into the proposition header (the black
bar) at the top of the site. It adds some custom SASS to override GOV.UK
template and align these navigation items to the right (because it looks
better).
It then removes the service chooser dropdown (and its associated SASS and JS) in
favour of a link alongside the user-related navigation items. ‘Switch service’
is the best language for this that we’ve come up with so far.
This means that the only way of adding a new service is from the `/services`
page. So this commit removes the redirect if you land on this page with only one
service (else it would prevent you from ever being able to add more).
This page is exactly the same as the page for adding your first service, save
the heading text.
So all this commit does is:
- set up two routes (`/add-service`, `/add-service/first`) for each of the two
journeys and change the existing journeys to use the `/add-service/first`
route
- add logic to show different heading text depending on the journey
- add a link to the new (`/add-service`) route in the service chooser dropdown
