This commit has a lot of stuff.  I added two new listeners on the server for when someone enters the room and for when the person leaves the room.  The enter listener can be used for when we want to send all of the messages to the user upon entry.  I also added one emitter which just sends out the updated list of current users in the chat room. The front end now has the ability to send code.  The buttons that show up in the chat window do not work yet. Also modified/reaaranged some methods and attributes in the objects.