refactored MsgSink and MsgSource

msg_talker.py

@@ -0,0 +1,15 @@
+from abc import ABC
+from msg_container import MsgContainer
+from msg_listener import MsgListener
+
+class MsgTalker(ABC):
+	def __init__(self):
+		self.sinks = []
+
+	def register_listener(self, sink: MsgListener):
+		self.sinks.append(sink)
+
+	def call_listener(self, msg: MsgContainer):
+		for sink in self.sinks:
+			if sink.is_msg(msg):
+				sink.on_recv(msg)