Name Change Helper Function
    - Add listener for nameAttempt events
    - Don't allow nicknames to begin with 'Guest'.
    - Register the name if it isnt already registered.
    - remove the previous name to make it available for other clients.
    - Send an error to the client if the name is already registered
add helper function to handle broadcasting of messages to other users
add helper function that handles new room assignment.
add helper function to handle client disconnection
Merge pull request #4 from arcin/socket_server

Name Change Helper Function