Update rollup to version 0.38.1 🚀

[greenkeeperio-bot]

Hello lovely humans,

rollup just published its new version 0.38.1.

State	Update 🚀
Dependency	rollup
New version	0.38.1
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 137 commits .

• 4e6b551 -> v0.38.1
• 3cc109c Merge pull request #1186 from rollup/gh-1176
• b59263e Merge pull request #1179 from kzc/drop-unused-inner-functions-and-classes
• d4a0e6e Merge pull request #1182 from vinkla/patch-1
• 2eebe3d deconflict function expression IDs (#1176)
• 8bd83f0 Simplify repository value
• 2744947 drop unused function and class declarations within functions (#1108, #1178)
• a9f342c Merge pull request #1174 from rollup/gh-595
• b624d67 remove, and warn about, unused imports from external modules (#595)
• 7b3402f Merge pull request #1173 from rollup/gh-492
• dbc4c48 Merge pull request #1172 from rollup/gh-444
• 58f9f26 support async functions (#492)
• 5f8205e warn on empty bundle (#444), and remove some tests that are no longer testing anything
• a502f30 add back @btd fix for #1104
• 47e712d Failling test for #1104

There are 137 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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