Increase MAX_ROUNDS 30 => 300

[frankier]

This is necessary to make my Minesweeper example work for larger sizes. In the current version mine placement takes n*mines rounds to coalesce where n is some small factor n=1..3. I don't know if there's the possibility of a more principled or better approach for this longer term (eg maybe this could be configurable somehow and the default could be 30) but I think a larger value might be good to tide things over until this is decided on.

[ibdknox]

Yeah, I think it's fine to raise this for now. The main thing that MAX_ROUNDS is there for is to handle the case where you loop infinitely - we want there to be some way to notify you that it happened and then bail out. There's a more complex mechanism we could use to do that (e.g. hash each timestep's state and if you encounter the same hash again you know you're looping), but that requires a lot of effort to implement.