Update README per recommendations from Seth:

sky/sdk/README.md

Index: sky/sdk/README.md
diff --git a/sky/sdk/README.md b/sky/sdk/README.md
index 4426c4d594bc8221a484d74dac2d026f2848dcf2..efbea286dfc8fa1387afc08a5e4594e56b8e8eed 100644
--- a/sky/sdk/README.md
+++ b/sky/sdk/README.md
@@ -32,9 +32,7 @@ The simplest Sky app is, appropriately, HelloWorldApp:
 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() {
@@ -64,10 +62,9 @@ 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());
 }
 ```