'Adds a message to the all_messages DiskList which is then used as
a source for drawing the graph.
@returns: True to keep calling it, and False when all it\'s done.'

def handle_message(self, msg):

    (yield super(LogGraph, self).handle_message(msg))
    mmseg = int((msg.get_real_time() * 1000))
    mtype = msg.get_type()
    if (mtype == 'vulnerability'):
        sever = msg.get_severity()
    else:
        sever = None
    self.all_messages.append((mmseg, mtype, sever))
