1 to 1 chat

[sanket0896]

• Get SocketId of each connection and save it
• Modify user list to contain more relevant data
• When user exits, socket should be deleted but not user data
• When user clicks on another user's name, the corresponding chat screen should open with previous chats.
• When user sends message in a particular user's chat screen, the message should reach the corresponding user.
• Message received from a user should only be visible in that user's chat screen.
• When message is receivd, sender's name in receivers user list should be highlighted.
• When highlighted user is clicked, it should be unhighlighted
• Add name field to Get username Screen
• Show Name and also username instead of only Username in User List