Updated CHANGELOG.

Author: mckaskle

CHANGELOG.md

@@ -1,3 +1,4 @@
-# [Unreleased](https://github.com/seedco/StackViewController/compare/0.4.0...HEAD)
+# [0.5.0](https://github.com/seedco/StackViewController/compare/0.4.0...0.5.0)
 
+- Upgrade to Swift 5.0.
 - Fix runtime crashes (unrecognized selector) by adding `@objc` annotation to public UIKit extensions.