RFC - The ProductName registry entry

[Bruno Jesus]

Louis Lenders sent the following url patch to fix bug #28065, it was
rejected because it fixes the product name so even if you set other
version inside winecfg the registry entry will still say "Windows XP".
http://www.winehq.org/pipermail/wine-patches/2011-August/105414.html

I have made a small change to winecfg to make it save the correct
ProductName based on the selected OS and would like comments.

If I ever send my patch to git Louis Lenders patch will need to get in
too because we would need a default ProductName setting in registry
and his patch was correct because the default wine OS is XP, am I
right?

The patch is quite simple and it tries to never let 2 ProductName
exist in different windows versions.

Thanks in advance,
Bruno