Upstreaming of basic material on `List.Pairwise` and `List.Nodup`. More
complete API to follow later, this is just a first approximation of what
leansat will need.
This will collect definitions from Std.Logic
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Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
