This patch removes most of the Windows x64 compilation warnings, although the majority is just disabled (only for Windows x64!) until we find a better solution. Additionally some math macro redefinition warnings are removed.
Win32 and x64 tests still run without reporting a problem.
There is still a warning (when compiling x64) in marketmodel.cpp, marketmodel_smm.cpp, marketmodel_cms.cpp, marketmodel_smmcaplethomocalibration.cpp, marketmodel_smmcapletcalibration.cpp, marketmodel_smmcapletalphacalibration.cpp each. It is about an implicit conversion from __int64 to QuantLib::Real in a std::copy operation, which can be avoided using a transform. Since I am not sure whether everybody will like that I will suggest an additional patch for those.