ls -f shows . and .. first

[bdrung]

ls -f should not sort directory entries. When using GNU ls the directories . and .. are somewhere in the unsorted list, but uutil's ls always shows . and .. first.

Bug-Ubuntu: https://launchpad.net/bugs/2117720

[Alonely0]

I know why this is the case and I don't like it. Our implementation lies and cheats; we just populate our internal directory list with the dot directories if necessary because std::fs::read_dir() does not include them. I can look into it within a couple of weeks, although I have to say that any possible fix to this will be contingent on #11465, as this issue is related to it.

EDIT: the fix for this issue is on that PR as well because otherwise the new tests fail :p