Adding three redirects for old Directgov PDFs

Approved by the content guys - Zen desk tickets:

https://govuk.zendesk.com/agent/#/tickets/509394
https://govuk.zendesk.com/agent/#/tickets/549886
Configure IPO for transition app
Configure monitor on transition app
Merge pull request #571 from rjc123/newmappings

Configure monitor on transition app
Merge pull request #569 from rjc123/admin

Add TLD generation tool
Merge pull request #570 from rjc123/newsites

Configure IPO for transition app
Merge pull request #568 from alphagov/add_some_directgov_pdf_mappings

Adding three redirects for old Directgov PDFs
Update monitor configuration with new alias and tld config
Merge pull request #572 from rjc123/newmappings

Add alias and revise monitor site configuration
Add alias to legacy VLA site
Configure cefas on transition app
Configure fera on transition app
Configure vmd on transition app
Configure naturalengland on transition app
Configure marine management organisation on transition app
Merge pull request #573 from rjc123/newsites

Configure several Defra agencies/albs on transition app
Configure darwin initiative on transition app
Configure RDPE on transition app
Configure Defra Smoke Control on transition app
Configure Defra Sustainable Development on transition app