first pass for #GridMapper version of #RandomDungeonGenerator - just one version, will be plenty of complications to handle

@kensanata Probably getting to where I can look at mappn the #ADnD #RandomDungeonGenerator output to #GridMapper Alex. Errors that are left so far are esoteric secret door things I haven't worked out yet and aren't really important. Even have a parallelised version, so made 1000 10 periodic check dungeons as a test earlier. Worked fine. Stats later!