Update rollup to version 0.39.2 🚀

[greenkeeperio-bot]

Hello lovely humans,

rollup just published its new version 0.39.2.

State	Update 🚀
Dependency	rollup
New version	0.39.2
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 rollup.
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 126 commits .

• a00d391 -> v0.39.2
• 04dbe12 Merge pull request #1205 from rollup/gh-1153
• 595fa58 prevent mutation of cached ASTs (#1153)
• 415985b -> v0.39.1
• 38bb9d9 Merge pull request #1204 from rollup/gh-1198
• d1d667f ignore var inits in dead branches - fixes #1198
• 11a2830 Merge pull request #1202 from rollup/gh-1082
• 532dff1 change recommendation to local installation of rollup-watch (#1082)
• c597b91 Merge pull request #1200 from rollup/gh-1197
• 708fb98 warn on missing format (fixes #1197)
• 979cfc2 update a few dependencies
• aa1c72a -> v0.39.0
• a53555d Merge pull request #1199 from rollup/gh-1194
• f695e62 richer warnings in CLI
• a44a171 update CLI to handle new warnings

There are 126 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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