Feature request: Recip trait

[clarfonthey]

Essentially, a pair to Neg for multiplication. Anything which can have its reciprocal taken would implement this. Useful in the context of Mul + Recip + One, for example.

[cuviper]

Sure, I could see this applicable to floating point, Complex, and Ratio at least.

It may also be useful for stuff like modular arithmetic and square matrices, although it would more often be called an "inverse" in those settings. Those may also want more control of failure modes, since it's not as simple as division by zero -- maybe with try/checked variants?

[clarfonthey]

@cuviper I agree, and while Inv might be a better name, recip is already used for most numbers and may be best. Also, even though "reciprocal matrix" is weird to say, it's not unheard of.