v0.11.0

Added

• An app can keep resources at a provider, such as a Cloudflare Worker, and
  get a token for each one. Declare a Resource class inside the service class,
  as you declare Settings. It has four steps: create, update, delete,
  and get_token. The app makes every other call with get_token() and the
  provider's SDK. When a manager manages the service card, Druks sends the four
  steps to the manager, and the app code does not change. A failed step raises
  ResourceError. resource.get_secrets() gives a sandbox the resource's token
  as a placeholder, such as CLOUDFLARE_API_TOKEN. Resource and
  ResourceError come from druks.services.