Request: Make CHENGELOG.md

[polisherm]

Thank you for developing git-sim.
I request you to make CHENGELOG.md in this repository.
Now, it is hard to check the diff from previous version to current version.

If you can, please do it.
Best regards,

[polisherm]

I did not know that changes per release already existed. I found it at the following URL.
https://github.com/initialcommit-com/git-sim/releases

Therefore, this Issue is closed.