The standard doesn't add them for local iterators, but I'm guessing that's an
oversight. So for now, I've hidden them behind a preprocessor condition. Which
I'll probably remove before review.
[SVN r2944]
unordered_multiset. I thought the proposed resolution for issue 528 allowed
them to be removed, but re-reading it, it only allows signatures that are
'otherwise indistinguishable', and they are not.
[SVN r2923]