Fix build issues (caused by email-validator)

package.json

@@ -21,7 +21,7 @@
   "license": "ISC",
   "dependencies": {
     "ajv": "^5.5.0",
-    "email-validator": "^1.1.1",
+    "email-validator": "^2.0.3",
     "i18n4v": "^0.2.2",
     "mithril": "^1.1.5",
     "polythene-css": "^1.0.0",

webpack.config.prod.js

@@ -11,16 +11,6 @@ const config = {
     filename: 'bundle.js',
   },
 
-  // To run development server
-  devServer: {
-    contentBase: __dirname,
-    publicPath: '/dist',
-    compress: true,
-    port: 9000,
-    hot: true,
-    index: 'index.html',
-  },
-
   module: {
     rules: [
       {