An object Message is now sent between clients and server (instead of a
string)
A message have a type to indicate if the message is a text or image
message.
The send and receive process now act accordingly to the type of the
message. For now, when it's an image message, the string "Image" is
displayed
Display message in bubble with the chat name. Image sending not
functional
Image sending fucntional but very slow
Need to redimenssion the image + optimize the bitmap-byteArray sequence