message: cargo: add metadata
  This adds Cargo manifest metadata, in preparation for the first release.
diff: [package]
  name = "zincati"
  version = "0.0.0-dev.0"
  +description = "Update agent for Fedora CoreOS"
  +license = "Apache-2.0"
  +keywords = ["cincinnati", "coreos", "fedora", "rpm-ostree"]
  authors = ["Luca Bruno <luca.bruno@coreos.com>"]
  +repository = "https://github.com/coreos/zincati"
  edition = "2018"
  [dependencies]
  @@ -29,3 +33,12 @@ tokio = "^0.1"
  [profile.release]
  lto = true
  +
  +[package.metadata.release]
  +sign-commit = true
  +upload-doc = false
  +disable-publish = true
  +disable-push = true
  +pre-release-commit-message = "cargo: zincati release {{version}}"
  +pro-release-commit-message = "cargo: development version bump"
  +tag-message = "zincati {{version}}"
  