cmd, dashboard: dashboard using React, Material-UI, Recharts (#15393)

* cmd, dashboard: dashboard using React, Material-UI, Recharts

* cmd, dashboard, metrics: initial proof of concept dashboard

* dashboard: delete blobs

* dashboard: gofmt -s -w .

* dashboard: minor text and code polishes

dashboard/assets/webpack.config.js

@@ -0,0 +1,36 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+const path = require('path');
+
+module.exports = {
+    entry:  './index.jsx',
+    output: {
+        path:     path.resolve(__dirname, 'public'),
+        filename: 'bundle.js',
+    },
+    module: {
+        loaders: [
+            {
+                test: /\.jsx$/, // regexp for JSX files
+                loader: 'babel-loader', // The babel configuration is in the package.json.
+                query: {
+                    presets: ['env', 'react', 'stage-0']
+                }
+            },
+        ],
+    },
+};