Fix for MAINT-7131 Unable to start the x64 Viewer on Windows 8.1 x64.  This appears to be because two of the MS DLLs we ship with the 64 bit viewer are 32bit. Manually replacing them with their 64 bit equivalents allowed the viewer to start on Windows 8.1.  The change forces the cmake file which copies the DLLs to look in C:\windows\SysWOW64 for 32 bit versions and C:\windows\system32 for 64 bit versions. (yes really).