Update README.md

Author: iosbrain

README.md

@@ -1,7 +1,7 @@
 # iOS File Management
 An Xcode 9 project written in protocol-oriented Swift 4 code to create a wrapper for the iOS FileManager class and API. 
 
-In this tutorial, I'm going to show you how to develop support for manipulating files inside your app's sandboxed directory structure -- _but_, my code has been designed and written in Swift by leveraging two relatively new methodologies: protocol-oriented programming (POP) and value semantics.
+In the [tutorial on my blog](http://iosbrain.com/blog/2018/04/22/ios-file-management-with-filemanager-in-protocol-oriented-swift-4/), I'm going to show you how to develop support for manipulating files inside your app's sandboxed directory structure -- _but_, my code has been designed and written in Swift by leveraging two relatively new methodologies: protocol-oriented programming (POP) and value semantics.
 
 Here's UML diagram showing the design of the protocol-oriented Swift code you'll find in the project: