Thread: merge last externally°locked evolution + async_funct.

git-svn-id: http://svn.boost.org/svn/boost/branches/release@84198 b8fc166d-592f-0410-95f2-cb63ce0dd405
context: merge from trunk


git-svn-id: http://svn.boost.org/svn/boost/branches/release@84199 b8fc166d-592f-0410-95f2-cb63ce0dd405