unbound blocklist updater

Purpose

Update unbound's blocklist automatically. Script is run from a cron job.

General overview

1. Fetches open source block lists
2. Parses lists according to unbound's syntax
3. Loads new list and runs config check
4. If config passes test then replace old versions and reload unbound service
5. If config fails, then remove the newest lists

What I am running

• FreeBSD 12.2-RELEASE on a raspberry pi 3b
• unbound-1.10.1

Block lists

These block lists are from multiple open source repos:

Homepage
https://github.com/blocklistproject/Lists
https://adaway.org/
https://github.com/Yhonay/antipopads

Uses shellcheck for posix compliance.