* Fix invalid build: key "_PULL_BASE_REF" in cloudbuild.yaml

* show environments from cloudbuild

* Move into kubernetes-sigs organization

* Disable labeler action for forks

* Fix docker build and delete vendor files which were not deleted

* Fix docker build and delete vendor files which were not deleted

* Add me as a owner

* Fix docker build and delete vendor files which were not deleted

* add "dyn" provider
* add several --dyn-* args to configure Dyn login
* add github.com/nesv/go-dynect/dynect@0.6.0 to Gopkg and vender/ (the client
  of choice by Terraform)
* make externdns.Version public so it can be stored when committing
  zone changes
* add tutorial for Ingress resources and update root README.md file

Dyn REST API is documented here: https://help.dyn.com/dns-api-knowledge-base/

Example usage:

  external-dns \
    --provider=dyn \
    --dyn-customer-name=acme \
    --dyn-username=acme-api \
    --dyn-password=t0pS3cr3t \
    --domain-filter=portal.acme.com \
    --zone-id-filter=acme.com \
    --namespace=my-test-ns \
    --log-level=debug \
    --txt-prefix=_

* feat(config): change defaults, switch flag processing to kingpin

* chore: vendor kingpin as a dependency

* feat(config): auto-detect cluster config from the environment

* chore: clean up definition of flags

* chore: sanitize flags even further

* chore: update changelog with latest flags changes

* fix(aws): fix messed up test name

* chore: build docker image with google container builder

* chore: add boilerplate header

* add makefile with coverage

* fix syntax, go get gocovmerge

verify runs the same verification as the CI runs.