Changelog for chatmail deployment

untagged

Install dig on the server to resolve DNS records (#267)
preserve notification order and exponentially backoff with retries for tokens where we didn't get a successful return (#265)
Run chatmail-metadata and doveauth as vmail (#261)
Apply systemd restrictions to echobot (#259)
re-enable running the CI in pull requests, but not concurrently (#258)

Move systemd unit templates to cmdeploy package (#255)
Persist push tokens and support multiple device per address (#254)
Avoid warning for regular doveauth protocol's hello message. (#250)
Fix various tests to pass again with "cmdeploy test". (#245, #242
Ensure lets-encrypt certificates are reloaded after renewal ([#244]) https://github.com/deltachat/chatmail/pull/244
Persist tokens to avoid iOS users loosing push-notifications when the chatmail metadata service is restarted (happens regularly during deploys) (#238
Fix failing sieve-script compile errors on incoming messages (#237
Fix quota reporting after expunging of old mails (#233