added a javascript build pipeline for transpiling and minifying; updated readme

javascript/webpack.config.js

@@ -0,0 +1,28 @@
+const path = require('path');
+
+module.exports = {
+    entry: {
+        zulma_navbar: './src/zulma_navbar.js',
+        zulma_search: './src/zulma_search.js',
+        zulma_switchcss: './src/zulma_switchcss.js'
+    },
+    output: {
+        filename: '[name].js',
+        path: path.resolve('../static/js')
+    },
+    module: {
+        rules: [{
+            test: /\.js$/,
+            exclude: /node_modules/,
+            use: ['babel-loader']
+        }]
+    },
+    resolve: {
+        extensions: ['*', '.js']
+    },
+    stats: {
+        colors: true
+    },
+    devtool: 'source-map',
+    mode: 'production',
+};