Update README to include images.

Author: paulyoung

README.md

@@ -1,4 +1,8 @@
 Statusfy
 ========
 
+<img src="https://raw.github.com/paulyoung/Statusfy/master/Statusfy/Images.xcassets/AppIcon.appiconset/icon_256x256.png" alt="Icon" width="256" height="256" />
+
 Spotify in your status bar.
+
+<img src="https://raw.github.com/paulyoung/Statusfy/master/screenshot.png" alt="Screenshot" width="439" height="67" />