Add react-native to dev dependencies

Author: stefvhuynh

package.json

@@ -55,6 +55,7 @@
     "react": "^16.0.0",
     "react-dom": "^16.0.0",
     "react-hot-loader": "^3.0.0-beta.2",
+    "react-native": "^0.50.4",
     "rimraf": "^2.5.4",
     "style-loader": "^0.19.0",
     "webpack": "^3.6.0",