Support webpack 4 (#64)

Author: Industrial

.travis.yml

@@ -1,6 +1,5 @@
 language: node_js
 node_js:
-  - 4
   - 6
   - 8
 branches:

example/package.json

@@ -16,8 +16,8 @@
     "koa": "^2.3.0",
     "react": "^16.0.0",
     "react-dom": "^16.0.0",
-    "webpack": "^3.7.1",
-    "webpack-dev-middleware": "^1.12.0",
+    "webpack": "^4.1.1",
+    "webpack-dev-middleware": "^3.0.1",
     "webpack-hot-server-middleware": "file:../"
   }
-}
+}

example/webpack.config.js

@@ -5,6 +5,7 @@ const dist = path.join(__dirname, 'dist');
 module.exports = [
     {
         name: 'client',
+        mode: 'development',
         target: 'web',
         entry: './client',
         output: {
@@ -14,6 +15,7 @@ module.exports = [
         devtool: 'source-map'
     }, {
         name: 'server',
+        mode: 'development',
         target: 'node',
         entry: './express/server',
         output: {