Add dupTop2 to Lorentz
Clarification and motivation
In some smart contracts we have the following helper:
dupTop2 :: a & b & f :-> a & b & a & b & f
dupTop2 = do
duupX @2
duupX @2
It looks generally useful, I propose to have it in Lorentz.
Acceptance criteria
An instruction that duplicates two topmost stack items is exported from Lorentz
.