Feature request: Support for dual keys/array sorting

[manofstick]

Hi @damageboy

I've had a little perusal at the code and I'm not sure if it can be done efficiently (but you are obviously more familiar with the whole thing), but would it be possible to support a signature like:

void Sort<TKey,TValue> (TKey[] keys, TValue[] items, ...);

(as this is what's needed to enhance my PR for Linq's Orderby).

In this file.