Add typedDict for RPC messages

Currently not fully functional.

freqtrade/rpc/telegram.py

@@ -30,6 +30,7 @@ from freqtrade.exceptions import OperationalException
 from freqtrade.misc import chunks, plural, round_coin_value
 from freqtrade.persistence import Trade
 from freqtrade.rpc import RPC, RPCException, RPCHandler
+from freqtrade.rpc.rpc_types import RPCSendMsg
 
 
 logger = logging.getLogger(__name__)
@@ -429,7 +430,7 @@ class Telegram(RPCHandler):
             return None
         return message
 
-    def send_msg(self, msg: Dict[str, Any]) -> None:
+    def send_msg(self, msg: RPCSendMsg) -> None:
         """ Send a message to telegram channel """
 
         default_noti = 'on'