Add JuMP function

[blegat]

According to jump-dev/JuMP.jl#3980 (comment), we should define set_forward_constraint_function etc.. that do the reshape and call moi_function and not do it in MOI.set like

DiffOpt.jl/src/jump_moi_overloads.jl

Line 21 in 43a8226

return MOI.set(model, attr, JuMP.moi_function(func))