updated changes.txt

Author: sanzmauro

client/CHANGES.txt

@@ -1,5 +1,9 @@
 CHANGES
 
+3.3.4 (Aug 19, 2020)
+- Added support for the new Split streaming architecture. When enabled (default), the SDK will not poll for updates but instead receive notifications every time there's a change in your environments, allowing to process those much quicker. If disabled or in the event of an issue, the SDK will fallback to the known polling mechanism to provide a seamless experience.
+- Updated the default of featuresRefreshRate to 60 seconds.
+
 3.3.3 (Apr 7, 2020)
  - Fix issue regarding special characters come from split/segments fetchers.