Add link to apps using SwiftyStoreKit on AppSight.

README.md

@@ -651,6 +651,7 @@ It would be great to showcase apps using SwiftyStoreKit here. Pull requests welc
 * [OB Monitor](https://itunes.apple.com/app/id1073398446) - The app for Texas Longhorns athletics fans
 * [Talk Dim Sum](https://itunes.apple.com/us/app/talk-dim-sum/id953929066) - Your dim sum companion
 
+A full list of apps is published [on AppSight](https://www.appsight.io/sdk/574154).
 
 ## License