[v3 patch] add C++11 allocator support to RB trees

[Jonathan Wakely <jwakely dot gcc at gmail dot com>]

This makes std::map, std::multimap, std::set and std::multiset
allocator-aware, leaving only std::list and std::deque that don't meet
the C++11 allocator requirements.

Also avoid some redundant zero-initialization of aligned_storage
buffers that are meant to be uninitialized, add a conditional noexcept
to std::vector, and extend allocator tests to cover move construction
and allocator-extended copy construction.

Tested x86_64-linux, committed to trunk.

Attachment: cl.txt
Description: Text document

Attachment: patch.txt
Description: Text document