[#41] Catch error 410 Gone to not retry

Closes #41 (closed)

• Sendpush will only throw an exception if error is temporary (503) so it will be retried.
• If error 410 (device does not accept notifications anymore) then specific log for later cleanup

For reference Webpush Error codes https://autopush.readthedocs.io/en/latest/http.html#error-codes