Update react in group default to the latest version 🚀 (#22)

## There have been updates to the *react* monorepo: 

- The `dependency` [react](https://github.com/facebook/react) was updated from `16.8.0` to `16.8.1`.
- The `dependency` [react-dom](https://github.com/facebook/react) was updated from `16.8.0` to `16.8.1`.
- The `devDependency` [react-test-renderer](https://github.com/facebook/react) was updated from `16.8.0` to `16.8.1`.

These versions are **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.

This monorepo update includes releases of one or more dependencies which all belong to the [react group definition](https://github.com/greenkeeperio/monorepo-definitions).

---

[Find out more about this release](https://github.com/facebook/react).

<details>
  <summary>FAQ and help</summary>

  There is a collection of [frequently asked questions](https://greenkeeper.io/faq.html). If those don’t help, you can always [ask the humans behind Greenkeeper](https://github.com/greenkeeperio/greenkeeper/issues/new).
</details>

---


Your [Greenkeeper](https://greenkeeper.io) bot 🌴

example/package.json

@@ -12,8 +12,8 @@
   "dependencies": {
     "@u-wave/translate": "^1.0.0",
     "ecstatic": "^3.0.0",
-    "react": "^16.8.0",
-    "react-dom": "^16.8.0"
+    "react": "^16.8.1",
+    "react-dom": "^16.8.1"
   },
   "devDependencies": {
     "@babel/core": "^7.0.0",

package.json

@@ -33,7 +33,7 @@
     "prop-types": "^15.6.1"
   },
   "peerDependencies": {
-    "react": "^16.8.0"
+    "react": "^16.8.1"
   },
   "devDependencies": {
     "@babel/core": "^7.0.0",
@@ -51,9 +51,9 @@
     "expect": "^24.0.0",
     "mocha": "^5.1.1",
     "nyc": "^13.0.1",
-    "react": "16.8.0",
-    "react-dom": "16.8.0",
-    "react-test-renderer": "16.8.0",
+    "react": "16.8.1",
+    "react-dom": "16.8.1",
+    "react-test-renderer": "16.8.1",
     "rollup": "^1.1.0",
     "rollup-plugin-babel": "^4.0.2"
   }