Implement SETVER.EXE driver and executable

[boeckmann]

Currently, no free SETVER implementation seems to exist for the EDR kernel, making version faking rely on the proprietary binary shipped with OpenDOS 7.01. The SETVER implementation for the FreeDOS kernel is incomplete. Only a minimal driver 1 seems to exist. FreeDOS seems to rely on a different methanism called CALLVER 2, which could be adapted, but works different.