Added missing <algorithm> include - fixes some problems when mixing boost with windows headers.

[SVN r21426]

include/boost/config/platform/win32.hpp

@@ -52,6 +52,7 @@
 #endif
 
 #ifdef BOOST_MSVC
+#include <algorithm> // for existing std::min and std::max
 namespace std{
   // Apparently, something in the Microsoft libraries requires the "long"
   // overload, because it calls the min/max functions with arguments of