Update flow-bin to the latest version � (#763)

Summary:
## The devDependency [flow-bin](https://github.com/flowtype/flow-bin) was updated from `0.115.0` to `0.117.0`.
This version 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.

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**Publisher:** [mvitousek](https://www.npmjs.com/~mvitousek)
**License:** MIT

[Find out more about this release](https://github.com/flowtype/flow-bin).

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Your [Greenkeeper](https://greenkeeper.io) bot 🌴
Pull Request resolved: https://github.com/facebook/flipper/pull/763

Reviewed By: passy

Differential Revision: D19621269

Pulled By: mweststrate

fbshipit-source-id: d213eeda19ba3715471f3843b38a8ae5d7a53713

.flowconfig

@@ -36,4 +36,4 @@ untyped-import
 untyped-type-import
 
 [version]
-0.115.0
+0.117.0