image tweaks, full applet casting complete, savebytes/strings to sketch

folder

core/PMethods.java

@@ -38,6 +38,8 @@ public interface PMethods {
   public void blend(PImage src, int sx1, int sy1, int sx2, int sy2, 
                     int dx1, int dy1, int dx2, int dy2, int mode);
 
+  public PImage copy();
+
   public void save(String filename);
 
   public void smooth();