Update chart.js to version 2.1.6 🚀

[greenkeeperio-bot]

Hello lovely humans,

chart.js just published its new version 2.1.6.

State	Update 🚀
Dependency	chart.js
New version	2.1.6
Type	devDependency

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 chart.js.
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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GitHub Release

Fixes an issue identified in V2.1.5 where returning arrays from tooltip callbacks was broken. #2775

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The new version differs by 1711 commits .

• 07662b1 V2.1.6 with tooltip array fix
• 0720608 Merge pull request #2776 from chartjs/fix/2775
• f106e1b fix tooltip with array returns
• 44e4004 Merge pull request #2760 from chartjs/2.1.5_release
• 3d03e36 Bump version to 2.1.5 and build
• 16a6555 Merge pull request #2758 from chartjs/fix/zoom-curved-lines
• f3d4ee9 Capping these to the chart bounds causes lines to bend during pan and zoom
• 5de72a1 Merge pull request #2755 from chartjs/fix/2751
• 7be69ce Fix pointLabel docs typo
• 647dc58 Merge pull request #2752 from simonbrunel/plugins-arch
• 53eb766 New datasets update plugin extensions
• dfdbd44 Allow to register/unregister an array of plugins
• a55c17d Enhance plugin notification system
• 7a419af Rename plugin service and notification method
• d901687 Remove link that doesn't exist anymore in scale docs

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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