Add trigger for unpatching on SIGTERM and SIGKILL

[HKunogi]

Currently if you cultivation gets closed by any abrupt way, the patching isn't undone, leading to the proxying to stay activate, leading to many problems on internet usage (like certificate validation). To solve that, one has to reopen cultivation and then launch the game from it, it will fail to patch, but then when closing the game properly, it will unpatch it. Adding triggers for abrupt interruptions and unpatching at that time would solve that issue.