Update @types/node to the latest version 🚀

[greenkeeper[bot]]

Version 9.3.0 of @types/node was just published.

Dependency	@types/node
Current Version	8.5.8
Type	devDependency

The version 9.3.0 is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

It might be worth looking into these changes and trying to get this project onto the latest version of @types/node.

If you have a solid test suite and good coverage, a passing build is a strong indicator that you can take advantage of these changes directly by merging the proposed change into your project. If the build fails or you don’t have such unconditional trust in your tests, this branch is a great starting point for you to work on the update.

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Your Greenkeeper bot :palm_tree:

[coveralls]

Coverage remained the same at 99.891% when pulling 7ec3bd8db96c62dfc3177d52ffe56c2522d9eb3b on greenkeeper/@types/node-9.3.0 into 6c0bacf4edc803c842c6cc54595d20c25c5c975c on master.

[coveralls]

Coverage remained the same at 99.891% when pulling 7ec3bd8db96c62dfc3177d52ffe56c2522d9eb3b on greenkeeper/@types/node-9.3.0 into 6c0bacf4edc803c842c6cc54595d20c25c5c975c on master.