test_excutor regression on msvc-10,11,12

[viboes]

Test output: teeks99-03d-win2008-64on64 - thread - ex_executor / msvc-11.0
Rev 86731 / Sat, 16 Nov 2013 21:43:27 +0000
Compile [2013-11-17 06:14:19 UTC]: fail



    call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\vc\vcvarsall.bat" x86 >nul
cl /Zm800 -nologo @"C:\local\teeks99-03\d\results\boost\bin.v2\libs\thread\test\ex_executor.test\msvc-11.0\debug\threading-multi\executor.obj.rsp" 

executor.cpp
C:\local\teeks99-03\d\boost\boost/thread/future.hpp(3796) : error C2440: '<function-style-cast>' : cannot convert from 'int (__cdecl *)(void)' to 'BF'
        No constructor could take the source type, or constructor overload resolution was ambiguous
        ..\libs\thread\test\..\example\executor.cpp(65) : see reference to function template instantiation 'boost::future<R> boost::async<boost::executor_adaptor<Executor>,int>(boost::executor_adaptor<Executor> &,R (__cdecl *)(void))' being compiled
        with
        [
            R=int,
            Executor=boost::thread_pool
        ]
            

[viboes]

Changeset [86744] seems to fixes this issue.