It would be good to have an option to skip multiple "is the same file" when copying directories containing hardlinks

[nkedel]

My use case:
1) I run a deduplicated backup which creates a hard link.
2) I use MC to consolidate directories. I have to skip on every hard-linked duplicate.
3) I would like NOT to have to acknowledge the error every time.

My preferred option would be to have a "skip all" option after the first error so that I could see duplicate files when I , but I can't figure out how to implement that.

I've implemented a general confirmation checkbox, and am using this patch; it's pretty self-contained. I'm attaching it and would be happy if you take it, but the "skip all" option would be even better if one off the regular devs feels like taking this. :D

[nkedel]

Patch to add a "skip same file errors" option to the confirmation dialog.

[nkedel]

Updated patch for 4.8.19, with change to gboolean