Merge pull request #2255 from FabrizioBrancati/master

Updating Swift.gitignore with Package.pins

Swift.gitignore

@@ -35,6 +35,7 @@ playground.xcworkspace
 #
 # Add this line if you want to avoid checking in source code from Swift Package Manager dependencies.
 # Packages/
+# Package.pins
 .build/
 
 # CocoaPods