Lance Roy

The only sort of norm defined is `Quadrance`, and its name makes it seem like it should satisfy the parallelogram identity and so define an inner product. It would be...

A group is only a Z-module when the group is abelian, as you need `(x*y)^2 == x^2 * y^2`. However, `ZeroRng` has `instance Group r => LeftModule Integer (ZeroRng r)`....

This PR adds documentation for the `_noclamp` functions from [this](https://github.com/jedisct1/libsodium/pull/1216) libsodium PR.