Full migration of port-win32 solution and project files to Visual Studio 2013

* Migrated project files to Visual 2013.
* Platform toolset set to v120_xp so we can target Windows XP and 2003 Server from msvc 2013 runtime.
* Set each project Intermediate Directory to exclusive directories so the compiler artifacts (e.g. .obj files) don't clash.
* Set a bin folder for each Configuration Type so the Release32 and Debug32 builds executables can exist in parallel

Item 3.2 in dibbler-user.pdf should updated as well.