Added Swift example to README

README.md

@@ -57,6 +57,22 @@ dispatch_async(_backgroundQueue, ^{
 });
 ```
 
+In Swift:
+
+```swift
+dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0) {
+            let node = ASTextNode()
+            node.attributedString = NSAttributedString(string: "hello")
+            node.measure(CGSize(width: screenWidth, height: CGFloat.max))
+            node.frame = CGRect(origin: CGPointZero, size: node.calculatedSize)
+            
+            // self.view isn't a node, so we can only use it on the main thread
+            dispatch_async(dispatch_get_main_queue()) {
+                self.view.addSubview(node.view)
+            }
+        }
+```
+
 AsyncDisplayKit at a glance:
 
 * `ASImageNode` and `ASTextNode` are drop-in replacements for UIImageView and