Added particle system example.

java/libraries/opengl/examples/Animation/ParticleSystem/ParticleSystem.pde

@@ -0,0 +1,27 @@
+PShape system;
+  
+void setup() {
+  size(500, 500, P3D);
+    
+  system = createShape(PShape.GROUP);
+    
+  for (int i = 0; i < 10; i++) {
+    PShape pt = createShape(POINT);
+    pt.strokeWeight(20);
+    pt.stroke(random(255), random(255), random(255));
+    pt.vertex(random(width), random(height));
+    system.addShape(pt);
+    pt.end();
+  }
+} 
+
+public void draw () {
+  background(255);
+
+  shape(system);
+    
+  for (int i = 0; i < system.getChildCount(); i++) {
+    PShape pt = system.getChild(i);
+     pt.translate(random(-5, 5), random(-5, 5), random(-5, 5));
+  }
+}