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

When using multiple OPC connections, prevents disconnected server(s)
from stalling the client.

Music not included this time, sadly.

- Colors from an image lookup table
- Tweaks to brightness, speed, initial conditions

Missed a commit, oops.