use region other than us-central1 for Google Cloud Functions

(Updated July 2018) Good news! Cloud Functions is now available in 4 different regions: Iowa (us-central1), South Carolina (us-east1), Tokyo (asia-northeast1), and Belgium (europe-west1).

To specify your region, you can specify --region during deploy, e.g.

$ gcloud functions deploy howdy --trigger-http --region=europe-west1