Add option to choose whether the deleted region should be added to kill ring

[blue0513]

This package is very useful 🎉 I'll suggest one more feature: related #13 , #12

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What's this PR

Add smart-hungry-delete-should-add-kill-ring method to choose whether deleted region should be added to kill ring or not.

Usage

Usage is as follows.

(use-package smart-hungry-delete
  :ensure t
  :init
  (smart-hungry-delete-add-default-hooks)
  (smart-hungry-delete-should-add-kill-ring nil) ;; or `t`

[blue0513]

Thx for the review!! 🤝 These days, unfortunately I'm a bit busy. So I'll respond later 🙇

[hrehfeld]

Sure, I'm happy to review when you find the time, thanks for submitting! <3