Append Medium link

Author: florentmorin

MailDemo.xcodeproj/project.xcworkspace/xcuserdata/florent.xcuserdatad/UserInterfaceState.xcuserstate

@@ -1,3 +1,7 @@
-#  Mail demo in SwiftUI
+#  Mail and message demo in SwiftUI
 
 You can send mail and message using SwiftUI and MessageUI in this simple source code.
+
+## The Medium publication
+
+If you want to know more, [there is a publication for that](https://medium.com/@florentmorin/messageui-swiftui-and-uikit-integration-82d91159b0bd) 😁