(PUP-3006) Block x64 installer on Windows 2003

- Block x64 installer from running on Windows 2003 with an unsupported message
and a suggestion to use the x86 version of the MSI.
Merge pull request #72 from ferventcoder/ticket/master/PUP-2964-block-win2003-x64

(PUP-3006) Block x64 installer on Windows 2003