Add optional parameter username to title variable (#6)

Author: styler

docs/chatbot/variables/title.md

@@ -11,7 +11,7 @@ Displays the channel’s title
 
 #### Parameters
 
-This variable does not take any parameters.
+- `username` (optional): The username of the account you want to check. If no username is provided, the command will return the title of the current channel.
 
 #### Example Input