Update yargs to the latest version 🚀

[greenkeeper]

Version 9.0.1 of yargs just got published.

Dependency	yargs
Current Version	8.0.2
Type	dependency

The version 9.0.1 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of yargs.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Commits

The new version differs by 24 commits.

• d1b23f3 chore(release): 9.0.1
• ac8088b fix: implications fails only displayed once (#954)
• 73be236 chore(release): 9.0.0
• 0e0c58d fix: strict mode should not fail for hidden options (#949)
• c240661 fix: address bug with handling of arrays of implications
• abdc7da feat: allow implies and conflicts to accept array values (#922)
• a9f03e7 feat: allow parse with no arguments as alias for yargs.argv (#944)
• 792564d feat: to allow both undefined and nulls, for benefit of TypeScript (#945)
• 71c7ec7 fix: exclude positional arguments from completion output (#927)
• a40cbc9 refactor: ES6ify (#937)
• 767d0d0 refactor: Use native Object.assign (#936)
• a2c0fef docs: correct typos in example.md (#934)
• 1d56df3 chore(package): Change engine node version to >=4 (#926)
• ab592c3 docs: add link to community slack (#930)
• 1ef44e0 feat: enable .help() and .version() by default (#912)

There are 24 commits in total.

See the full diff

Not sure how things should work exactly?

There is a collection of frequently asked questions and of course you may always ask my humans.

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Your Greenkeeper Bot 🌴

[coveralls]

Coverage remained the same at 100.0% when pulling 60545fb on greenkeeper/yargs-9.0.1 into 2e801fe on master.