execution_monitor.ipp #warning directive breaks compilation on MSVC 8.0

[Stjepan Rajko]

This problem is occuring in CVS HEAD using MSVC 8.0:

In execution_monitor.ipp, the line:

# warning Debugger check disabled. Either define _WIN32_WINNT or include Boost.Test header in front of winbase.h

breaks compilation with

boost/test/impl/execution_monitor.ipp(60) : fatal error C1021: invalid preprocessor command 'warning'

On MSVC, the following would work instead:

# pragma message("Warning: Debugger check disabled. Either define _WIN32_WINNT or include Boost.Test header in front of winbase.h")

[Gennadiy Rozental]

fixed