Update yargs to version 6.6.0 🚀

[greenkeeperio-bot]

Hello lovely humans,

yargs just published its new version 6.6.0.

State	Update 🚀
Dependency	yargs
New version	6.6.0
Type	dependency

This version 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.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 436 commits .

• e5613f0 chore(release): 6.6.0
• 19a897b refactor: use process.stdout.columns instead of window-size (#737)
• 66573c8 feat: split demand() into demandCommand()/demandOption() (#740)
• 5883779 feat: implement conflicts() for defining mutually exclusive arguments; thanks @madcampos! (#741)
• f755e27 fix: [object Object] was accidentally being populated on options object (#736)
• 27e1a57 feat: support for positional argument aliases (#727)
• 9bdaab7 fix: do not use cwd when resolving package.json for yargs parsing config (#726)
• 51af0a6 chore(release): 6.5.0
• 702995a feat: pull in yargs-parser introducing additional settings (#688), and fixing #716 (#722)
• 30a9492 fix: still freeze/unfreeze if parse() is called in isolation (#717)
• 84c69cc docs: use https for image URL at README.md (#718)
• 00d6513 chore(package): update nyc to version 10.0.0
• 6d17938 chore(package): update nyc to version 9.0.1
• bf6707e chore(release): 6.4.0
• 8507390 chore: add camelcase to greenkeeper ignore, until we drop 0.10 support (#704)

There are 250 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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