Don't rely on xdelta3 python module

Don't crash if xdelta3 module is not present, and add the ability to download game & voicepack in CLI
Bump to 1.2.8

worthless/patcher.py

@@ -1,7 +1,5 @@
 import os
 import platform
-
-import xdelta3
 import tarfile
 import appdirs
 from pathlib import Path
@@ -12,6 +10,12 @@ from worthless import constants
 from worthless.launcher import Launcher
 from worthless.installer import Installer
 
+NO_XDELTA3_MODULE = False
+try:
+    import xdelta3
+except ImportError:
+    NO_XDELTA3_MODULE = True
+
 
 class Patcher:
     def __init__(self, gamedir=Path.cwd(), data_dir: str | Path = None, patch_url: str = None, overseas=True):
@@ -147,7 +151,7 @@ class Patcher:
             f.write(patched_xlua_bytes)
 
     def apply_xlua_patch(self, fallback=True):
-        if fallback:
+        if NO_XDELTA3_MODULE or fallback:
             asyncio.run(self._patch_xlua_fallback())
             return
         self._patch_xlua()
@@ -161,7 +165,7 @@ class Patcher:
         :return: None
         """
         # Patch UnityPlayer.dll
-        if fallback:
+        if NO_XDELTA3_MODULE or fallback:
             asyncio.run(self._patch_unityplayer_fallback())
         else:
             self._patch_unityplayer()