Set FileVersion = GForcePackageVersion when present

[sparr]

I'll be blunt... I don't remember why I made this change. I am confident it was the shortest path I could find to load some file I was pulling game audio out of, months to years ago, but that's all I can remember. I'm cleaning up my local source tree and wanted to preserve this for posterity. I won't be offended if you close this; it will still be findable when someone hits the same problem in the future and comes searching for a solution.