Update README.md

Author: amyyong11

README.md

@@ -43,6 +43,7 @@ Each of us have created one or more PRs and most of these have been merged into
 - The App Screen UI is the screen that acts as a proxy between the user's login screen and their individual chats
 - Upon logging in, a user will will be rendered with a view of app screen
 - App screen provides an ordered list of a user's chats and also allows a user to create new chats
+- Each chat button will also display a date indicating the date of the last message in a chat's conversation history, or no date if a chat has no messages 
 - ChatView (the window referenced above) will open upon clicking an existing chat to display the chats's GUI
 - With respect to ChatView, clicking on the +Private Chat and +Group Chat buttons will also open an instance of ChatView for a user to create a new chat