Brings DNSControl up to date along with some new features

[plttn]

Few things here:

• Updates DNSControl to the latest version (as 3.31.4 came out quite a while ago)
• Improves the output of the preview to remove color codes, resulting in there not being color codes in the preview comment (without disabling color for the action logs)
• switches it to use concurrent as that's about to be the default.

Personal bugbear that isn't a huge deal:

With concurrent mode on, the preview looks like this:

CONCURRENTLY gathering 1 zone(s)
SERIALLY gathering 2 zone(s)
Serially Gathering: "example.org"
Serially Gathering: "example.net"
Waiting for concurrent gathering(s) to complete...DONE
******************** Domain: example.com
******************** Domain: example.net
******************** Domain: example.org
2 corrections (porkbun)
#1: + CREATE example.org A 1.1.1.1 ttl=600
#2: + CREATE demo.example.org A 1.1.1.1 ttl=600
Done. 2 corrections.

With concurrent off, it looks like this:

******************** Domain: example.com
******************** Domain: example.net
******************** Domain: example.org
2 corrections (porkbun)
#1: + CREATE example.org A 1.1.1.1 ttl=600
#2: + CREATE demo.example.org A 1.1.1.1 ttl=600
Done. 2 corrections.

I couldn't quite figure out how to get grep to drop those first few lines, but feel free to amend the PR if you can get it sorted.

[tlimoncelli]

The grep -v statements can be removed. Those are only output if the --full flag is used, which it isn't.

[tlimoncelli]

Instead of the sed, you can use ``--no-color` (it goes before the "preview" or "push" verb).

I would also add:

• --reportmax=0 -- be less verbose

[plttn]

The reason I implemented it like this was so that colors still worked in the action log, but weren't commented in the PR.

[tlimoncelli]

ah! makes sense.

(it's a shame that whoever added the -p flag to col didn't also strip escape sequences)

[SukkaW]

@plttn It seems that the dnscontrol-action is no longer maintained. Would you like to take over and maintain it? I am more than happy to use your fork instead!