ed9986def6
Fix it so that emails are (hopefully) able to show the one-click unsubscribe button in Gmail and other mail providers that support the List-Unsubscribe header. This way users can unsubscribe instead of marking emails as spam. * Add the List-Unsubscribe-Post header. * Fix the disable email notifications endpoint to support POST as well as DELETE requests. * Fix the disable email notifications endpoint to disable XSRF protection (we don't need users to be logged in because we use a signed URL instead). https://www.rfc-editor.org/rfc/rfc8058#section-3.1 https://www.rfc-editor.org/rfc/rfc8058#section-8.1