Find a site without having to type the www. portion of it

- Often, we type "direct.gov.uk" instead of "www.direct.gov.uk" into
  the search box, or similar sites, out of habit and are confronted
  with the Transition 404 page as "direct.gov.uk" without "www." at
  the front does not exist. Users might think of this site as the same
  thing, so we should make non-www site searches in Transition redirect
  to their www counterparts which are consistent everywhere, to avoid
  confusion of "but direct.gov.uk and www.directgov.uk are the same?!"
- This checks whether the site is found as the user entered it. If not,
  it prefixes the host with www. and tries the query again, falling back
  on 404 if it really can't find it (e.g. [www.]thisisnotasite.gov.uk).