div() and rem()

now `div()` and `rem()` are not supported:
```
julia> x = Dual(1.1, 2.2);

julia> y = Dual(3.3, 4.4);

julia> div(y, x)
ERROR: MethodError: no method matching div(::Dual128, ::Dual128, ::RoundingMode{:ToZero})

julia> rem(y, x)
ERROR: MethodError: no method matching rem(::Dual128, ::Dual128)
```

how could we handle these functions?
thanks