Add weback-dev-server with hot/hmr support

* adds `npm start` / `yarn start` script
* starts a webpack-dev-server using the dev config, served on :3333
* hot reloading (HMR) for react/styles, not working for angular code
* new entry `dev.ts` for dynamic imports of CSS theme (ExtractText does
not work with HMR)
* TS loader pipeline moved out of common to add HMR for react
* applied `hot()` to some react containers (that's their new default
 export, named exports remains for testing)
* added sections to README
* updated yarn.lock

scripts/webpack/webpack.test.js

@@ -9,8 +9,16 @@ config = merge(common, {
     'react/lib/ExecutionEnvironment': true,
     'react/lib/ReactContext': true,
   },
-  node: {
-    fs: 'empty'
+  module: {
+    rules: [
+      {
+        test: /\.tsx?$/,
+        exclude: /node_modules/,
+        use: [
+          { loader: "awesome-typescript-loader" }
+        ]
+      },
+    ]
   },
   plugins: [
     new webpack.SourceMapDevToolPlugin({