Add retries to protocol queries (#65)

* Add retries to query(), defaults to 3 + add tests

* Catch also json decoding errors for retries

* add missing exceptions file, fix old protocol tests

kasa/smartdevice.py

@@ -19,7 +19,8 @@ from datetime import datetime, timedelta
 from enum import Enum
 from typing import Any, Dict, List, Optional
 
-from kasa.protocol import TPLinkSmartHomeProtocol
+from .exceptions import SmartDeviceException
+from .protocol import TPLinkSmartHomeProtocol
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -47,10 +48,6 @@ class WifiNetwork:
     rssi: Optional[int] = None
 
 
-class SmartDeviceException(Exception):
-    """Base exception for device errors."""
-
-
 class EmeterStatus(dict):
     """Container for converting different representations of emeter data.