Add events for sniffing the WebSocket data

Add on_socket_raw_receive and on_socket_raw_send events for sniffing the
data being received and sent on the websocket. Useful for debugging and
logging websocket messages received and sent on the link to Discord's
servers.

discord/client.py

@@ -93,7 +93,12 @@ class WebSocket(WebSocketBaseClient):
     def handshake_ok(self):
         pass
 
+    def send(self, payload, binary=False):
+        self.dispatch('socket_raw_send', payload, binary)
+        WebSocketBaseClient.send(self, payload, binary)
+
     def received_message(self, msg):
+        self.dispatch('socket_raw_receive', msg)
         response = json.loads(str(msg))
         log.debug('WebSocket Event: {}'.format(response))
         if response.get('op') != 0: