We sometimes need to call secure webhooks that require API keys or parameters that are dynamically set during the build.
It would be great to add the ability to:
a) set a parameter from the environment variables
b) set a header so it could support AWS API Gateway
notify: webhooks: # A list of hook hashes, containing the URL field - url: https://example.com/hooks/circle - header: "x-api-key:$API_KEY"