fclones-gui: add custom flags field

[kapitainsky]

e.g. now using GUI it is not possible to specify hash to be used during grouping.

There are and always will be plenty of things GUI is maybe missing.

Universal solution would be to add custom flags field so I could add e.g. --hash-fn blake3

Easy to use is great idea but should not limit other users:) Otherwise you will be soon flooded with issues - I need flagX - I need flag Y etc.

custom flags - will make everybody contented at least if not happy

[kapitainsky]

And thank you for providing GUI - I have just tested on macOS - works like a charm even thought GTK looks like from another planet:) But I think it is ok for easy cross platform solution.

[pkolaczk]

Thanks for testing! Happy to hear it works fine on a system I never tried. Yes, I believe it looks alien on macOS, but at least it looks good on Ubuntu ;)

As for the feature request, I'll think about it - definitely a reasonable and not a hard thing to do. However first I need to make sure the duplicates panel understands symlinks to avoid accidental data loss.

[kapitainsky]

sure - It is freshly baked so for sure you have some icing to do before extra features can be considered. Still I believe that this one is low hanging fruit to avoid never ending requests for "missing flags"