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:

[tusharmath]

observable-air@ benchmark /home/travis/build/tusharmath/observable-air tsc; node ./benchmarks/run

Node: v9.3.0 V8: 6.2.414.46-node.15

┌─────────────────────────────────────────────────────┬─────────────────┬─────────┐
│ name                                                │ ops/sec         │ samples │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ create                                              │ 740 (±1.01%)    │ 86      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> debounce                                    │ 1,005 (±4.71%)  │ 60      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> combine(sum3, [a, b, c]) -> reduce(sum2, 0) │ 82,717 (±2.42%) │ 71      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> map -> reduce                               │ 48 (±4.07%)     │ 76      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> scan -> reduce                              │ 25 (±3.27%)     │ 60      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> takeN(0, n/10)                              │ 387 (±3.27%)    │ 80      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ array(2) -> array(i) -> switchLatest                │ 6,280 (±3.73%)  │ 69      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ tryCatch                                            │ 1,169 (±1.07%)  │ 91      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ file -> mergeMap                                    │ 41 (±1.6%)      │ 65      │
├─────────────────────────────────────────────────────┼─────────────────┼─────────┤
│ (file, file) -> concat                              │ 20,836 (±1.88%) │ 79      │
└─────────────────────────────────────────────────────┴─────────────────┴─────────┘

[coveralls]

Coverage remained the same at 89.041% when pulling 88de789ebf7b1a842b8745a182cc6ab6df1f799e on greenkeeper/@types/node-9.3.0 into af33fb1e2a5325727a9339265b68b41656eea8ca on master.