[cvsnt] MSI installer error for custom install

[Tony Hoyle]

David Somers wrote:
> Ow double crap... HKLM/Software/CVS/PServer/InstallPath now include multiple
> locations... please consider putting the location of the common files in a
> separate key.

installpath just points to cvs.exe (ideally it should point to the root 
install directory not a subdirectory of it, but I left it there for 
compatibility).

There seems to be a bug that puts the common files directory there too 
but that shouldn't be there.  Nothing needs to know that..

Tony