The "zigzag" argument is handy to create daisy-chained grids, but what
if we want to start from the other side? I don't think rotation gets us
there, but this does.

Replace deprecated registerDraw with registerMethod. Call sleep statically.

Update all Processing sketches to use the OPC.pde version from
grid24x8z_clouds that uses background/async socket management, and
doesn't grid to a halt every time the server drops out