Leaving the old vars here for compatibilty.  They can be removed at some future time.

This also means an update to java-8.

  - restore a GoCD server backup
  - backup a GoCD server config via cron and bash script
go-server backup is performed using a separate backup user.
To change admin or backup user credentials, process is now to change
the sandbox-secure repo passwords and re-run ansible provisioning.
The passwords are written into go-server after the restore.

The headers were pointing to the old github wiki. Since we've officially
moved to Confluence, these links should be updated.