Update imagemin-pngquant to the latest version 🚀

[greenkeeper[bot]]

The dependency imagemin-pngquant was updated from 7.0.0 to 8.0.0.

This version is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

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Release Notes for v8.0.0

Breaking:

• Require Node.js 8 7049509

v7.0.0...v8.0.0

Commits

The new version differs by 4 commits.

• 61997a2 8.0.0
• 7049509 Require Node.js 8
• 6ce8a90 Use Travis to test on Windows (#57)
• 97c4d23 Fix the default documented value for the speed option (#55)

See the full diff

FAQ and help

There is a collection of [frequently asked questions](https://greenkeeper.io/faq.html). If those don’t help, you can always [ask the humans behind Greenkeeper](https://github.com/greenkeeperio/greenkeeper/issues/new).

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Your Greenkeeper bot :palm_tree:

[codecov[bot]]

Codecov Report

Merging #80 into master will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #80   +/-   ##
=======================================
  Coverage   94.73%   94.73%           
=======================================
  Files           5        5           
  Lines         190      190           
=======================================
  Hits          180      180           
  Misses         10       10

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