Redirect manual/alerts/email-alerts.html to its new location
Redirect manual/alerts/email-alerts.html to its new location

- This is good practice, for "no link left behind", and infinitely
  easier than deploying Puppet across all three environments to fix the
  alert link itself.

alphagov/govuk-developer-docs,alphagov/govuk-developer-docs,alphagov/govuk-developer-docs,alphagov/govuk-developer-docs