Improve Sky READMEs

TBR=ojan@chromium.org

Review URL: https://codereview.chromium.org/1037163002

examples/README.md

+Sky Examples
+============
+
+This directory contains several examples of using Sky.
+
+1. *Hello, world.* The [hello world app](hello_world) is a basic app that shows
+   the text "hello, world."
+
+2. *Stocks.* The [stocks app](stocks) is an example of a typical mobile app
+   built using Sky. The app shows a list of all the stocks in the NASDAQ.
+
+3. *Widgets.* The [widgets app](widgets) contains a number of Sky widgets so
+   you can experiment with them in a simple container.

examples/hello_world/hello_world.dart

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:sky/framework/fn.dart';
+
+class HelloWorldApp extends App {
+  Node build() {
+    return new Text('Hello, world!');
+  }
+}

examples/hello_world/main.sky

+<script>
+import 'hello_world.dart';
+
+void main() {
+  new HelloWorldApp();
+}
+</script>

examples/stocks/main.sky

@@ -8,7 +8,7 @@
 <script>
 // TODO(abarth): Should this be package:stocks/stocks_app.dart?
 import 'lib/stock_app.dart';
-main() {
+void main() {
   new StocksApp();
 }
 </script>

examples/stocks/pubspec.yaml

 name: stocks
 author: Chromium Authors <sky-dev@googlegroups.com>
 description: A demo application using Sky that shows stock data
-homepage: https://github.com/domokit/mojo/tree/master/sky/examples/stocks-fn
+homepage: https://github.com/domokit/sky_sdk/tree/master/examples/stocks
 version: 0.0.1
 dependencies:
   sky: '>=0.0.1 <1.0.0'

examples/widgets/main.sky

@@ -8,7 +8,7 @@
 <import src="/sky/framework/debug/shake-to-reload.sky" />
 <script>
 import 'widgets_app.dart';
-main() {
+void main() {
   new WidgetsApp();
 }
 </script>