Ensure patcher program can start on Windows

Windows doesn't quite have a concept of process forking, so to prevent
endlessly creating new processes, at this code.

Fix up for 614d475

sims2_4k_ui_patcher.py

@@ -935,6 +935,8 @@ def __init__(self):
 
 
 if __name__ == "__main__":
+    multiprocessing.freeze_support()  # Required for Windows
+
     app = QApplication(sys.argv)
     window = PatcherApplication()