message: cargo: add homepage
  This adds the homepage field to Cargo manifest, pointing it to the
  auto-built pages.
  Ref:
diff: name = "zincati"
  version = "0.0.13-alpha.0"
  description = "Update agent for Fedora CoreOS"
  +homepage = "https://coreos.github.io/zincati"
  license = "Apache-2.0"
  keywords = ["cincinnati", "coreos", "fedora", "rpm-ostree"]
  authors = ["Luca Bruno <luca.bruno@coreos.com>"]
  