Stop using the deprecated std::random_shuffle, for the benefit of MSVC.

And generalize `hrandom_shuffle` to take an arbitrary `Iter`,
so that passing `vec.begin()` will work even with MSVC's
debug iterators. (Passing `&vec[0]` or `vec.data()` would work
either way, but I'd worry that someone would forget to do that
conscientiously every time.)

hyper.h

@@ -37,7 +37,6 @@ using std::imag;
 using std::stable_sort;
 using std::out_of_range;
 using std::get;
-using std::random_shuffle;
 using std::move;
 using std::make_tuple;