Converted convex_hull to the multi-stage approach and made it variant-aware.

git-svn-id: http://svn.boost.org/svn/boost/trunk@86401 b8fc166d-592f-0410-95f2-cb63ce0dd405
According to the discussion on the ML, changed the default WinAPI back to XP.

git-svn-id: http://svn.boost.org/svn/boost/trunk@86403 b8fc166d-592f-0410-95f2-cb63ce0dd405
Refs #9291. Corrected the docs wrt the problems of using attribute keywords with phoenix::bind or phoenix::function.

git-svn-id: http://svn.boost.org/svn/boost/trunk@86404 b8fc166d-592f-0410-95f2-cb63ce0dd405
coroutine: documentation update


git-svn-id: http://svn.boost.org/svn/boost/trunk@86406 b8fc166d-592f-0410-95f2-cb63ce0dd405