Add png type validation and create it

Author: Lucas Rojas

lib/manifestTools/manifestCreator/scrapers/icojs/src/ico.js

@@ -38,6 +38,7 @@ function buf2hex(buffer) { // buffer is an ArrayBuffer
  * @param {ArrayBuffer} buffer The ArrayBuffer object contain the TypedArray of a ICO file.
  * @returns {Object} PNG icon object.
  */
+
 function createPng(index, buffer) {
   var dv = new DataView(buffer);
 
@@ -77,14 +78,12 @@ function checkIfIsPNG(index, buffer) {
  * @returns {Object} An icon object.
  */
 function createIcon(bit, width, height, buffer) {
-
   return {
     bit:  bit,
     width: width,
     height: height,
     buffer: buffer
   }
-
 }
 
 var factory = function(config) {