Update webpack for examples

packages/babel-plugin-react-native-web/package.json

@@ -4,6 +4,7 @@
   "description": "Babel plugin for React Native for Web",
   "main": "index.js",
   "devDependencies": {
+    "babel-core": "^6.26.3",
     "babel-plugin-tester": "^5.0.0"
   },
   "author": "Nicolas Gallagher",

packages/examples/package.json

@@ -17,8 +17,8 @@
     "babel-plugin-react-native-web": "0.9.13",
     "babel-plugin-transform-runtime": "^6.23.0",
     "file-loader": "^1.1.11",
-    "webpack": "^4.8.1",
-    "webpack-bundle-analyzer": "^2.11.1",
-    "webpack-cli": "^2.1.3"
+    "webpack": "^4.28.3",
+    "webpack-bundle-analyzer": "^3.0.3",
+    "webpack-cli": "^3.1.2"
   }
 }