Fix texture packs

dungeonbattle/display/texturepack.py

@@ -7,6 +7,9 @@ class TexturePack:
     FLOOR: str
     PLAYER: str
 
+    ASCII_PACK: "TexturePack"
+    SQUIRREL_PACK: "TexturePack"
+
     def __init__(self, name: str, **kwargs):
         self.name = name
         self.__dict__.update(**kwargs)