Lowercase URLs if they are all capitals
Lowercase URLs if they are all capitals

Currently we serve 404s to users that have inadvertently entered a URL
with CAPSLOCK on. This commit downcases URLs that contain no lowercase
letters but ignores urls where the case is mixed.

This should reduce 404s received by users.

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet