Error messages in Xerces are generated by tools\NLS\Xlat, which currently runs
on windows. 

Here are the steps:
1) Modify XMLErrList_EN_US.Xml as per the changes
2) Build xerces with the CMake option: -Dxmlch-type=wchar_t and install it.
3) Using Visual C++, compile all the files in tools\NLS\Xlat and link them all into an
   executable (Xlat.cpp has the main()).
       i. You will need to set the include path to the <install location>\include.
       ii. You will need to specify the library directory for linking to <install location>\lib.
       iii. You will need to link to the appropriate xerces-c_*.lib file.
4) Set the PATH to <install location>\bin, that is, where xerces-c*.dll resides.
   Then noting the parameters for passing to the Xlat executable:
     /SrcRoot=x:/xerces-c/ /OutPath=x:/output/ /OutFmt=XXX /Locale=EN_US
     (trailing slashes for the paths are required)
     where:
        i. SrcRoot should point to XERCESCROOT, the root of the git repository.
       ii. OutPath should be any output folder that stores the generated files and must already exist.
      iii. Run the Xlat executable four times replacing /OutFmt=XXX with
           /OutFmt=Win32RC, /OutFmt=CppSrc, /OutFmt=ResBundle, /OutFmt=MsgCat.

5) Updated files will be generated and must be copied to their appropriate location.
   Tweak the copy commands below replacing x:\xerces\ with the path given to /OutPath earlier:

     copy x:\output\root.txt src\xercesc\util\MsgLoaders\ICU\resources\root.txt
     copy x:\output\XercesMessages_en_US.hpp src\xercesc\util\MsgLoaders\InMemory\XercesMessages_en_US.hpp
     copy x:\output\XercesMessages_en_US.Msg src\xercesc\util\MsgLoaders\MsgCatalog\XercesMessages_en_US.Msg
     copy x:\output\XMLDOMMsg.hpp src\xercesc\util\XMLDOMMsg.hpp
     copy x:\output\XMLErrorCodes.hpp src\xercesc\framework\XMLErrorCodes.hpp
     copy x:\output\XMLExceptMsgs.hpp src\xercesc\util\XMLExceptMsgs.hpp
     copy x:\output\XMLMsgCat_Ids.hpp src\xercesc\util\MsgLoaders\MsgCatalog\XMLMsgCat_Ids.hpp
     copy x:\output\XMLValidityCodes.hpp src\xercesc\framework\XMLValidityCodes.hpp

Note: If you run Xlat on windows, and are commiting them under unix, you must
      first run dos2unix on them. 
