deps: upgrade npm to 6.7.0

[zkat]

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Where this should land

• Node 11
• Node 10
• Node 8

Notable Changes

This PR supersedes #25551 and includes two releases. This is a significant change because it includes a major rework of the networking layer of npm and a rewrite of many subcommands. This, for example, removes npm-registry-client entirely in favor of npm-registry-fetch and libnpm. We've had to fix a couple of regressions since 6.6.0 came out, and we expect a few others to pop up, but nothing of huge impact has popped up, and they tend to be minor hiccups.

Other changes of note:

• 02c837e01 #106 Make npm dist-tags the same as npm dist-tag ls. (@isaacs)

• 1065a7809 #65 Add support for IBM i. (@dmabupt)

• 8543fc357 pacote@9.4.0: Fall back to "fullfat" packuments on ETARGET errors. This will make it so that, when a package is published but the corgi follower hasn't caught up, users can still install a freshly-published package. (@zkat)

• Another reminder that we've moved our issue tracking! You can read more about our move away from GitHub for issue tracking on our blog

Changelogs

• 6.6.0
• 6.7.0

/cc @MylesBorins

[MylesBorins]

It appears v6.7.0 was published 6 days ago meaning that this would be good to land on Feb 6th

@zkat do you think we should give this a bit longer to wait before landing on LTS? For the record we have semver-minor releases for 8.x and 10.x planned for mid / late march, perhaps that would be a good timeline?

[zkat]

I'd rather get this merged sooner tbh.

[MylesBorins]

It looks to me that 6.7.0 was published 3 days again. That's what I'm seeing on npmjs.org @zkat does that sounds right? If so then we can land this Feb 21st. I could have sworn it was already published when I checked last, so come clarity here would be appreciated.

It seems that the r.c. for 6.8.0 is what was published 3 days ago. This is ready to land after test suite is run

[MylesBorins]

CI: https://ci.nodejs.org/job/node-test-pull-request/20716/

edit: arm failure unrelated, rerunning for posterity

https://ci.nodejs.org/job/node-test-commit-arm-fanned/6399/

[MylesBorins]

LGTM

[MylesBorins]

Here is an output of running npx license-checker --summary

├─ MIT: 242
├─ ISC: 106
├─ BSD-2-Clause: 11
├─ Apache-2.0: 8
├─ BSD-3-Clause: 4
├─ Artistic-2.0: 4
├─ (WTFPL OR MIT): 3
├─ AFLv2.1,BSD: 1
├─ (MIT OR Apache-2.0): 1
├─ MIT*: 1
├─ Apache 2.0: 1
├─ (BSD-2-Clause OR MIT OR Apache-2.0): 1
├─ (BSD-2-Clause OR MIT): 1
├─ CC-BY-3.0: 1
├─ CC0-1.0: 1
└─ Unlicense: 1

[MylesBorins]

landed in 43dd49c