• BREAKING CHANGE: geoipupdate stops updating on the first error.
• A config file can now be used to configure the Docker image. This was
  documented but was not functional. Fixed by Shizun Ge. GitHub #433.
• NewUpdater in the unexported internal/geoipupdate package no longer
  mutates http.DefaultTransport when a proxy is configured. The CLI is the
  only caller, so there is no user-visible behavior change. Reported by B.
  Conners. GitHub #488.
• Do not retry proxy CONNECT 4xx errors. These are now treated as permanent
  failures.