Update resize_filter.class.js

Add better to toObject support

src/filters/resize_filter.class.js

@@ -293,6 +293,18 @@
         }
       }
       return img2;
+    },
+
+    /**
+     * Returns object representation of an instance
+     * @return {Object} Object representation of an instance
+     */
+    toObject: function() {
+      return { type: this.type,
+               scaleX: this.scaleX,
+               scaley: this.scaleY,
+               resizeType: this.resizeType,
+               lanczosLobes: this.lanczosLobes };
     }
   });