Merge from trunk.

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r86152 | chris_kohlhoff | 2013-10-04 09:59:54 +1000 (Fri, 04 Oct 2013) | 1 line

Fix WinRT detection.
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r86153 | chris_kohlhoff | 2013-10-04 10:00:46 +1000 (Fri, 04 Oct 2013) | 1 line

Add WinRT implementation notes.
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r86154 | chris_kohlhoff | 2013-10-04 10:03:36 +1000 (Fri, 04 Oct 2013) | 1 line

Fix dead links in documentation.
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r86462 | chris_kohlhoff | 2013-10-27 09:32:01 +1100 (Sun, 27 Oct 2013) | 1 line

Suppress conversion warnings reported by MSVC.
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r86463 | chris_kohlhoff | 2013-10-27 09:35:32 +1100 (Sun, 27 Oct 2013) | 1 line

Support older versions of OpenSSL that don't supply SSL_CTX_clear_options.
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r86464 | chris_kohlhoff | 2013-10-27 09:39:23 +1100 (Sun, 27 Oct 2013) | 1 line

Add a note to clarify that concurrent invocation is not guaranteed for handlers in different strands.
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r86465 | chris_kohlhoff | 2013-10-27 09:42:53 +1100 (Sun, 27 Oct 2013) | 1 line

Fix typos in spawn() documentation.
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r86468 | chris_kohlhoff | 2013-10-27 09:49:17 +1100 (Sun, 27 Oct 2013) | 1 line

Updated revision history.
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git-svn-id: http://svn.boost.org/svn/boost/branches/release@86470 b8fc166d-592f-0410-95f2-cb63ce0dd405
Regnerated string_ref docs. Fixed incorrect example. Fixes #8002


git-svn-id: http://svn.boost.org/svn/boost/branches/release@86488 b8fc166d-592f-0410-95f2-cb63ce0dd405
Merge 86392 from trunk. The spirit change was not applied because the file is not present in branches/release.

git-svn-id: http://svn.boost.org/svn/boost/branches/release@86489 b8fc166d-592f-0410-95f2-cb63ce0dd405
Merge 86398 which supplies a file missing from 86392.

git-svn-id: http://svn.boost.org/svn/boost/branches/release@86490 b8fc166d-592f-0410-95f2-cb63ce0dd405