build(defaults): update to v1.6.0

[joshwiens]

• Updates to minimum Node version of 4.8 ( npm 5 compatibility )
• Update devDependencies via npm run webpack-defaults
• Semantic changes to both CI configurations

[codecov]

Codecov Report

Merging #652 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #652   +/-   ##
=======================================
  Coverage   87.41%   87.41%           
=======================================
  Files           7        7           
  Lines         302      302           
  Branches       68       68           
=======================================
  Hits          264      264           
  Misses         36       36           
  Partials        2        2

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[felixjung]

Why was this not listed as a breaking change in the release notes? Our build is now failing because of the Node version requirement 😢

[michael-ciniawsky]

The node version bump itself is within the semver minor range, I know it's annoying in your case, but we needed to bump it bc of npm@5 and we simply can't release any nitty-gritty as semver major. It's assumed that folks use the @latest within their current semver major range