[Patch] Implement is_[nothrow_]swappable (p0185r1)

[Jonathan Wakely]

On 17/05/16 20:39 +0200, Daniel Krügler wrote:
>This is an implementation of the Standard is_swappable traits according to
>
>http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0185r1.html
>
>During that work it has been found that std::array's member swap's exception
>specification for zero-size arrays was incorrectly depending on the value_type
>and that was fixed as well.

This looks good to me, I'll get it committed (with some adjustment to
the ChangeLog format) - thanks.