Added: Sound.pde to manage sound --- the "musical" accompaniement.
       Responder.pde to maanage mouse clicks, key presses, etc.

Improved: code organization.
Major code cleaning.
Forgot to commit added file SerialManager.pde
Forgot to commit switchBank.pde.
Deleted Main.pde and put its code in Seurat.
Added square shape.
Installed SEStar shape.
Installed no fill, stroke only square option.
Minor code changes, reformat all.
Minor stuff