chore(package): update webpack to version 4.3.0

Closes #5

Author: greenkeeper[bot]

package.json

@@ -57,7 +57,7 @@
     "vue-loader": "^14.1.1",
     "vue-style-loader": "^4.0.2",
     "vue-template-compiler": "^2.5.3",
-    "webpack": "^3.8.1",
+    "webpack": "^4.3.0",
     "webpack-dev-middleware": "^2.0.5",
     "webpack-hot-middleware": "^2.20.0",
     "webpack-merge": "^4.1.1",