Make %ProductVer% readable from a file

[Mike Linacre]

We coordinate our version numbers across SUF, VB, Fortran, HTML, .rc, etc., and all these can be kept in step by writing "include"-type files, except SUF.

SUF version numbers have (?) to be entered manually with each version change.

A nice feature would be for SUF to read a variable list from an include file, e.g.,

%ProductVer% = 3.36.3
%TagLine% = "Now with even more bugs!"