Core: change how required versions work, deprecate IgnoreGame (#426)

`AutoWorld.World`s can set required_server_version and required_client_version properties. Drop `get_required_client_version()`.
`MultiServer` will set an absolute minimum client version based on its capability (protocol level).
`IgnoreVersion` tag is replaced by using `Tracker` or `TextOnly` with empty or null `game`.
Ignoring game will also ignore game's required_client_version (and fall back to server capability).

worlds/alttp/__init__.py

@@ -43,6 +43,7 @@ class ALTTPWorld(World):
     data_version = 8
     remote_items: bool = False
     remote_start_inventory: bool = False
+    required_client_version = (0, 3, 2)
 
     set_rules = set_rules
 
@@ -324,9 +325,6 @@ class ALTTPWorld(World):
             new_name = base64.b64encode(bytes(self.rom_name)).decode()
             multidata["connect_names"][new_name] = multidata["connect_names"][self.world.player_name[self.player]]
 
-    def get_required_client_version(self) -> tuple:
-        return max((0, 3, 2), super(ALTTPWorld, self).get_required_client_version())
-
     def create_item(self, name: str) -> Item:
         return ALttPItem(name, self.player, **as_dict_item_table[name])