Update dependency rollup to v1.27.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
rollup	devDependencies	minor	1.26.4 -> 1.27.0

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Release Notes

rollup/rollup

### [`v1.27.0`](https://togithub.com/rollup/rollup/blob/master/CHANGELOG.md#​1270) [Compare Source](https://togithub.com/rollup/rollup/compare/v1.26.5...v1.27.0) _2019-11-12_ ##### Features - Add support for output-specific plugins ([#​3218](https://togithub.com/rollup/rollup/issues/3218)) - Reenable parallel output processing when using the CLI ([#​3218](https://togithub.com/rollup/rollup/issues/3218)) - Warn if files are emitted that would overwrite previously emitted files ([#​3218](https://togithub.com/rollup/rollup/issues/3218)) ##### Bug Fixes - Do not overwrite files emitted in other builds if outputs are generated in parallel ([#​3218](https://togithub.com/rollup/rollup/issues/3218)) ##### Pull Requests - [#​3218](https://togithub.com/rollup/rollup/pull/3218): Per output plugins ([@​lukastaegert](https://togithub.com/lukastaegert)) ### [`v1.26.5`](https://togithub.com/rollup/rollup/blob/master/CHANGELOG.md#​1265) [Compare Source](https://togithub.com/rollup/rollup/compare/v1.26.4...v1.26.5) _2019-11-11_ ##### Bug Fixes - Fix a regression where it was no longer to pass a certain option format to generate ([#​3223](https://togithub.com/rollup/rollup/issues/3223)) ##### Pull Requests - [#​3223](https://togithub.com/rollup/rollup/pull/3223): Allow passing input options to output ([@​lukastaegert](https://togithub.com/lukastaegert))

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