Improved and cleaned up imports

src/pyrmv/classes/board.py

@@ -1,10 +1,10 @@
 from datetime import datetime
 from typing import Any, List, Mapping, Union
 
-from pyrmv.classes.journey import Journey
-from pyrmv.classes.message import Message
-from pyrmv.classes.stop import Stop
-from pyrmv.utility import ref_upgrade
+from ..classes.journey import Journey
+from ..classes.message import Message
+from ..classes.stop import Stop
+from ..utility import ref_upgrade
 
 
 class LineArrival: