Update dependencies

webpack.config.js

@@ -5,6 +5,7 @@ const HtmlWebpackPlugin = require('html-webpack-plugin');
 const CopyWebpackPlugin = require('copy-webpack-plugin');
 const CleanWebpackPlugin = require('clean-webpack-plugin');
 const webpack = require('webpack');
+var webpackMode;
 
 function makeClosureCompiler() {
     const externDir = path.join(__dirname, "externs");
@@ -54,6 +55,9 @@ var plugins = [
 
 if (process.env.PRODUCTION) {
     plugins.push(makeClosureCompiler());
+    webpackMode = "production";
+} else {
+    webpackMode = "development";
 }
 
 
@@ -72,6 +76,7 @@ module.exports = {
     resolve: {
         extensions: ['.ts', '.tsx', '.js']
     },
+    mode: webpackMode,
     module: {
         rules: [
             {