update the Windows instructions

ReadMe.cygwin

-#-------------------------------------------------------------
-# running configure
-#-------------------------------------------------------------
-
-To build for Windows Visual C++, configure with CXX=cl CC=cl:
-/full/path/to/configure --prefix=<install directory> CXX=cl CC=cl
-
-#-------------------------------------------------------------
-# setup the compiler
-#-------------------------------------------------------------
-
-For the compilation under cygwin using VC++, you have to make sure that 
-the PATH contains the path to the installation of Visual Studio.  
-The safest way to do this, is to add VC to your Cygwin.bat file.  
-Since it is possible to have several different versions of VC on the same 
-machine, we recommend keeping a generic Cygwin.bat and creating special 
-CygwinXXX.bat file for each compiler you want to use.  
-
-Here is an example for VC9:
-
-   @echo off
-
-   @call "C:\Program Files\Microsoft Visual Studio 9.0\VC\bin\vcvars32.bat"
-   @set PATH=%PATH%;C:\cygwin\bin
-
-   C:
-   chdir C:\cygwin\bin
-
-   bash --login -i
-
-Two lines, "@call..." and "@set...", have been added to the default Cygwin.bat.
-
-#-------------------------------------------------------------
-# setting the path explicitly for VC 7.1
-#-------------------------------------------------------------
-
-For the compilation under cygwin using VC 7.1 (Version 13.10.3077)
-you have to make sure that the PATH contains the path to the
-installation of Visual Studio .NET 2003, for example:
-
-export VSPATH="/cygdrive/c/Program Files/Microsoft Visual Studio .NET 2003"
-
-export PATH="/cygdrive/c/WINNT/Microsoft.NET/Framework/v1.1.4322":${PATH}
-
-export PATH="${VSPATH}/SDK/v1.1/bin":${PATH}
-export PATH="${VSPATH}/Common7/Tools/bin":${PATH}
-export PATH="${VSPATH}/Common7/Tools/bin/prerelease":${PATH}
-export PATH="${VSPATH}/Common7/Tools/":${PATH}
-
-export PATH="${VSPATH}/Vc7/bin":${PATH}
-export PATH="${VSPATH}/Common7/IDE":${PATH}
-
-The compiler also needs the following variables set up (and 
-as these are interpreted by the compiler, they have to be in 
-"windows-syntax"):
-
-export INCLUDE="c:/Program Files/Microsoft Visual Studio .NET 2003/Vc7/include;C:\Program Files\Microsoft Visual Studio .NET 2003\SDK\v1.1\include"
-export LIB="c:/Program Files/Microsoft Visual Studio .NET 2003/Vc7/lib;C:\Program Files\Microsoft Visual Studio .NET 2003\SDK\v1.1\Lib"
-
-You may have to adapt to your installation path, if different.
-
-#-------------------------------------------------------------
-# trouble reports
-#-------------------------------------------------------------
-
-Please report problems using the bug-tracker of the savannah portal at: 
-
-http://savannah.cern.ch/projects/clhep
-

ReadMe.win

+#-------------------------------------------------------------
+
+You MUST use cmake to build on a Windows machine.
+
+Work in a DOS window.
+
+#-------------------------------------------------------------
+# setup the compiler
+#-------------------------------------------------------------
+
+call "C:\Program Files\Microsoft Visual Studio 9.0\VC\bin\vcvars32.bat"
+
+#-------------------------------------------------------------
+# building CLHEP
+#-------------------------------------------------------------
+
+Work from a separate build directory.
+
+cmake -DCMAKE_INSTALL_PREFIX=C:\....
+      -G "NMake Makefiles"
+      -DCMAKE_BUILD_TYPE=RelWithDebInfo  
+       C:\full\path\to\CLHEP
+
+nmake
+
+nmake test
+
+nmake install
+
+#-------------------------------------------------------------
+# trouble reports
+#-------------------------------------------------------------
+
+Please report problems using the bug-tracker of the savannah portal at: 
+
+http://savannah.cern.ch/projects/clhep
+