Fix small typo in comments

the logic in 4ed23f44 for taking backups more often was partly backward

This reverts commit b32cb622.

Fixes #627. Fixes #653. Closes #714.

Fix a typo in Readme

`matchs` → `matches`

Provisioning could crash if, e.g., the DNS we see is different from the DNS Let's Encrypt sees.

see #695, probably fixes it

Added a warning to the installation / setup script

See pull request #638 and issue #635 for more information.

before the user agrees to Let's Encrypt's ToS the admin could get a nightly email with weird interactive text

Made a mistake refactoring the headless variable earlier.

fixes #696

https://discourse.mailinabox.email/t/status-check-emails-empty-after-upgrading-to-v0-16/1082/3

A user on that thread suggests an alternate solution, adding `PYTHONIOENCODING=utf-8` to `/etc/environment`. Python docs say that affects stdin/out/err. But we also use these environment variables elsewhere to ensure that config files we read/write are opened with UTF8 too. Maybe all that can be simplified too.

Duplicity gives times in UTC. We were assuming times were in local time.

Fix: Correct IP is reported when using custom DNS

Fix bug that reports wrong ip, when custom DNS is enabled

tls control panel: only show integral seconds while waiting the requested time from Lets Encrypt, in case we got back a non-integral number of seconds to wait

bind postfix to the right network interface when sending outbound mail so that SPF checks on the receiving end will pass

fixes #3 (again)

fixed typo

Updated according to Josh's latest reaction. Sounds good.

Same result as maximal_queue_lifetime and bounce_queue_lifetime, but complies with rfc2821.

The default timeout for Postfix's maximal_queue_lifetime and bounce_queue_lifetime is 5 days. This is way too long if you expect someone to have an answer and after 5 days you'll get the message that it's not delivered. This disrupts communication. It would be more responsive if the user got the 'can't deliver' error after 24 hours.

Removes border and rounded corners from navbar