Add icon to windows executable file

[Tarek-Hasan]

First, thanks for the new release. v3.1 looks better and runs smoothly compared to v2.7.

As I mentioned in the original issue of old StuntRally repo - in windows without integrated icons, stuntrally exe and shortcut files looks like corrupted or missing.

Hope, you'll fix this soon.

[cryham]

Yeah I know. Icons are also missing for Linux binaries and in Windows installer too. I didn't care much about those. Will add to roadmap and try doing someday.