fix(package): update react to version 16.4.0

Closes #384

Author: greenkeeper[bot]

package.json

@@ -71,7 +71,7 @@
     "lodash": "4.17.4",
     "mkdirp": "0.5.1",
     "npm-run-all": "4.0.2",
-    "react": "15.6.1",
+    "react": "16.4.0",
     "react-addons-css-transition-group": "15.6.0",
     "react-addons-test-utils": "15.6.0",
     "react-dom": "15.6.1",