Change to minimal Webpack output

This changes Webpack to only output errors, warnings, or new compilations.
This has the effect of hiding the massive list of modules. The giant list was
actually _hiding_ warnings because they appear first and scroll off the
terminal.

webpack.config.js

@@ -337,10 +337,9 @@ module.exports = (env, argv) => {
             // serve unwebpacked assets from webapp.
             contentBase: './webapp',
 
-            stats: {
-                // don't fill the console up with a mahoosive list of modules
-                chunks: false,
-            },
+            // Only output errors, warnings, or new compilations.
+            // This hides the massive list of modules.
+            stats: 'minimal',
 
             // hot module replacement doesn't work (I think we'd need react-hot-reload?)
             // so webpack-dev-server reloads the page on every update which is quite