Polynomial interpolation

Is polynomial interpoaltion in scope for this library? I thought about adding [Lagrange](https://en.wikipedia.org/wiki/Lagrange_polynomial) and [Hermite interpolation](https://en.wikipedia.org/wiki/Hermite_interpolation). The types could be
```hs
lagrange :: (G.Vector v a, Eq a, Fractional a) => [(a, a)] -> Poly v a

hermite :: (G.Vector v a, Eq a, Fractional a) => [(a, [a])] -> Poly v a
```