Feature - Fencing of sprites

This change requires that the pull request for scratch-render (Feature
fencing #82) be taken first

src/sprites/rendered-target.js

@@ -170,6 +170,7 @@ RenderedTarget.prototype.setXY = function (x, y) {
     this.x = x;
     this.y = y;
     if (this.renderer) {
+        this.renderer.getFencedPositionOfDrawable(this.drawableID, this);
         this.renderer.updateDrawableProperties(this.drawableID, {
             position: [this.x, this.y]
         });