Update CHANGELOG.md

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ## Unreleased
 ### Added
 - Support for external tile sets.
+- B3DM support for RTC_CENTER.
 
 ### Fixed
 - Add a readable message for when console.assert fails.