updated changelog

Author: Benjas333

README.md

@@ -86,7 +86,8 @@ client.run(token="YOUR TOKEN HERE")
 - Find an optimized way to send big files quickly.
 
 ## Changelog
-- Added loop() method to Selfbot class and token as an init argument.
+- Added rate limit support for the Webhook mode.
+- Added loop() method to Selfbot class and token as an init class argument.
 - Added multiple extensions implementation
 - Added multiple Discord channels implementation
 - Added seconds argument (default: 1)