Adding VCIncludeDir and WindowsSDKDir to the msbuild configuration file.  This allows clang to find windows.h and other files in the 
sdk and visutal studio includes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189528 91177308-0d34-0410-b5e6-96231b3b80d8