Update changelog

CHANGELOG.md

@@ -1,12 +1,18 @@
 # Changelog
 All notable changes to this project will be documented in this file.
 
-## [] - 0000-00-00
+## [1.4.0] - 2020-11-22
 ### Fixed
 - If authorization with last.fm is rejected, the unauthorized state is now
   immediately visible in the settings dialog, and the session key is discarded.
 - The preferences page now correctly handles re-authorization (#17).
 
+### Changed
+- Updated foobar2000 SDK to 2020-07-28
+- Updated cpprestsdk
+- Internal cleanup
+
+
 ## [1.3.1] - 2018-08-18
 ### Fixed
 - Disabling Now Playing notifications is now correctly honored.