(from AES) Merge pull request #1519 from datawire/alexgervais/dev/ambassador-base-push-backup
(from AES) Merge pull request #1519 from datawire/alexgervais/dev/ambassador-base-push-backup

Documenting how to build and push the ambassador-base image to backup container registries
datawire/ambassador,datawire/ambassador,datawire/ambassador,datawire/ambassador,datawire/ambassador