Update acorn to version 3.3.0 🚀

[greenkeeperio-bot]

Hello lovely humans,

acorn just published its new version 3.3.0.

State	Update 🚀
Dependency	acorn
New version	3.3.0
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 acorn.
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 148 commits .

• 693c5fe Mark release 3.3.0
• db34768 Update to fix optimization pass under Closure Compiler.
• 549b4ba Update to unicode 9.0.0
• 72b9024 Re-enable Bublé for building the bin and loose parser files
• aa20bf8 simplify rollup config using new paths option
• 5e5e430 Fix ES2016 check for "use strict".
• 0d38744 Slightly adjust patch a062434d4
• a062434 Implements ES2016 check for "use strict"
• 3dfa6a8 Drop 0.10 from travis.yml
• 8c3a881 remove babel-core/register
• 3aa428e remove build-acorn script
• ff5d23d bundle with Rollup
• 54fde50 Fix handling of [,] in toAssignableList.
• 6bad526 Added modern node versions to travis ci
• 7323217 Fix misbracketed call to isIdentifierChar.

There are 148 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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[traviskaufman]

@Garbee @sgomes wdyt about merging this into 1.x? Looks like CI passed with it.

[sgomes]

LGTM!