Adding CircleCI 1.0 config into our 2.0 config to support tag builds.
Adding CircleCI 1.0 config into our 2.0 config to support tag builds.

For context see:

- https://discuss.circleci.com/t/build-on-tag/9864/30
- https://discuss.circleci.com/t/git-tag-deploys-in-2-0/9493/8
- https://circleci.com/gh/keybits/circulate/58#config/containers/0

tseaver/google-cloud-python,dhermes/gcloud-python,tartavull/google-cloud-python,GoogleCloudPlatform/gcloud-python,dhermes/google-cloud-python,dhermes/gcloud-python,tseaver/google-cloud-python,jonparrott/gcloud-python,tseaver/gcloud-python,GoogleCloudPlatform/gcloud-python,jonparrott/gcloud-python,jonparrott/google-cloud-python,tswast/google-cloud-python,jonparrott/google-cloud-python,tswast/google-cloud-python,googleapis/google-cloud-python,tseaver/google-cloud-python,calpeyser/google-cloud-python,tartavull/google-cloud-python,dhermes/google-cloud-python,tswast/google-cloud-python,calpeyser/google-cloud-python,googleapis/google-cloud-python,dhermes/google-cloud-python,tseaver/gcloud-python