converting arguments object into true array for setters, restored the original underscore.js methods, and moved radius conversion logic from the setAttrs method to a radiusChange event listener in Ellipse

src/shapes/Sprite.js

@@ -29,6 +29,12 @@ Kinetic.Sprite = function(config) {
     };
     // call super constructor
     Kinetic.Shape.apply(this, [config]);
+
+    var that = this;
+    this.on('animationChange', function() {
+        // reset index when animation changes
+        that.setIndex(0);
+    });
 };
 /*
  * Sprite methods