Make the redirector build fail if any hosts are uppercase
Condense unique and lowercase checks into one

- This is so we don't iterate over all the hosts twice as this would
  cause the build to slow down.
Centralise `require`s in `lib/redirector`

* Make `test_helper` require that and any minitest dependencies
* To fix an environment-sensitive require order build failure
Rename the host validation rake task and methods to just be `validates`
Use the positive `uppercase.any?` instead of negative `.empty?`

- This makes it more readable.
- Also rename `uppercase` to `has_uppercase` - otherwise it sounds like
  a true/false value.
- Use `Set.new` instead of defining a hash for `has_uppercase` -
  slightly shorter and we weren't using the right hand side of the hash.
Add the Government Procurement Service as an alias of CCS

- Following a chat with Robin, this is deemed the best way of
  configuring the Government Procurement Service's domain
  gps.cabinetoffice.gov.uk as it appears idential to the new
  ccs.cabinetoffice.gov.uk domain content-wise, and currently,
  pre-transition, it redirects to CCS. The Government Procurement
  Service has closed down.
Update FERA's TNA Timestamp
Merge pull request #1013 from adammaddison/master

Update FERA's TNA Timestamp
Merge pull request #1011 from alphagov/configure_gps.cabinetoffice.gov.uk

Add the Government Procurement Service as an alias of CCS
Merge pull request #1012 from rjc123/newsites

Add special redirect strategy for decc restats
Config to Stabilisation Unit org on GOV.UK
Merge pull request #1014 from adammaddison/master

Config to Stabilisation Unit org on GOV.UK
Configure Natural England's MyEnvironment site
Merge pull request #1015 from alphagov/configure_naturalengland_myenvironment

Configure Natural England's MyEnvironment site
Merge pull request #1006 from alphagov/build_fails_if_uppercase_host

Make the redirector build fail if any hosts contain uppercase characters
redirector is now called transition-config
Rename modules and classes to TransitionConfig
Merge pull request #1017 from alphagov/rename_redirector

Rename redirector
Remove obsolete tld config

We now have IP addresses for our CDN which we use instead of having this
jury-rigged nginx config.
Fix typo