Update README per recommendations from Seth:

sky/sdk/README.md

 Sky
 ===
 
 Sky is an experimental, high-performance UI framework for mobile apps. Sky helps
 you create apps with beautiful user interfaces and high-quality interactive
 design that run smoothly at 120 Hz.
 
 Sky consists of two components:
 
 1. *The Sky engine.* The engine is the core of the system. Written in C++, the
@@ skipping 14 matching lines @@
 
 Examples
 --------
 
 The simplest Sky app is, appropriately, HelloWorldApp:
 
 ```dart
 import 'package:sky/framework/fn.dart';
 
 class HelloWorldApp extends App {
-  UINode build() {
-    return new Text('Hello, world!');
-  }
+  Node build() => new Text('Hello, world!');

[Hixie, 2015/04/15 19:10:30]

The reason not to do this is that in 99% of cases, this body will be bigger, and
so if we're expecting people to use this as a copypasta template, this is just
giving them more work (they'll have to put the curlies back).

[sethladd, 2015/04/15 19:20:19]

Totally fair.

 }
 
 void main() {
   new HelloWorldApp();
 }
 ```
 
 Execution starts in `main`, which creates the `HelloWorldApp`. The framework
 then marks `HelloWorldApp` as dirty, which schedules it to build during the next
 animation frame. Each animation frame, the framework calls `build` on all the
 dirty components and diffs the virtual `UINode` hierarchy returned this frame with
 the hierarchy returned last frame. Any differences are then applied as mutations
 to the physical hierarchy retained by the engine.
 
 For more examples, please see the [examples directory](examples/).
 
 Services
 --------
 
 Sky apps can access services from the host operating system using Mojo. For
 example, you can access the network using the `network_service.mojom` interface.
 Although you can use these low-level interfaces directly, you might prefer to
 access these services via libraries in the framework. For example, the
 `fetch.dart` library wraps the underlying `network_service.mojom` in an
 ergonomic interface:
 
 ```dart
 import 'package:sky/framework/net/fetch.dart';
 
-void main() {
-  fetch('example.txt').then((Response response) {
-    print(response.bodyAsString());
-  });
+void main() async {

[Hixie, 2015/04/15 19:10:30]

does this work? I sent feedback to dart-discuss asking for void async functions
but last I heard they had declined to support this.

[sethladd, 2015/04/15 19:20:19]

good catch. I should have removed the void annotation.

+  var response = await fetch('example.txt');
+  print(response.bodyAsString());
 }
 ```
 
 Set up your computer
 --------------------
 
 1. Install the Dart SDK:
   - https://www.dartlang.org/tools/download.html
 
 2. Install the ``adb`` tool from the Android SDK:
@@ skipping 19 matching lines @@
 3. Using a USB cable, plug your phone into your computer. If prompted on your
    device, authorize your computer to access your device.
 
 Running a Sky application
 -------------------------
 
 1. ``packages/sky/lib/sky_tool --install examples/stocks/main.sky``
    The --install flag is only necessary the first time to install SkyDemo.apk.
 
 2.  Use ``adb logcat`` to view any errors or Dart print() output from the app.