add new 'add' method to OpenLayers.Pixel -- eventually this will replace addX, addY, and addSize.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@48 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Util.js

@@ -114,6 +114,18 @@ OpenLayers.Pixel.prototype = {
         return new OpenLayers.Pixel(this.x, this.y+h);
     },
 
+    /** Return a new Pixel with this pixel's x&y augmented by 
+    *    the int values passed in.
+    * 
+    * @param {int} x
+    * @param {int} x
+    * 
+    * @return {OpenLayers.Pixel}
+    */
+    add:function(x, y) {
+        return new OpenLayers.Pixel(this.x + x, this.y + y);
+    },
+
     ////////////////////
     who:function(){return "OpenLayers.Pixel";}
 };