chore(package): update react to version 15.4.2 (#683)

package.json

@@ -66,7 +66,7 @@
     "mkdirp-then": "1.2.0",
     "mz": "2.6.0",
     "path-match": "1.2.4",
-    "react": "15.4.1",
+    "react": "15.4.2",
     "react-dom": "15.4.1",
     "react-hot-loader": "3.0.0-beta.6",
     "send": "0.14.1",