Update to RunExit tool

This is an update to the RunExit tool I created a few years ago for Windows 3. The original tool just plain ran the program and waited for it to complete. It didn't set the working directory for the program it ran (which messed up some programs, such as the games from Microsoft's Best of Entertainment pack) and didn't pass parameters, which may limit the usefulness in some other cases.

I've now updated the tool so it does both. For instance, you might run a game with a command line parameter like so:

win c:\runexit\runexit c:\games\mygame\mygame.exe /cheatmode

That starts Windows, which in turn starts RunExit, which then runs MYGAME.EXE in the directory C:\\GAMES\\MYGAME and passes it /cheatmode on its command line. After the game exits, RunExit shuts down Windows, returning to the DOS Prompt.