code: function crawlHref($,result, a, callback) {
  
        var link = $(a).attr('href');
        var parentUrl = result.url;
        if (link) {
  
          var anchor = $(a).text() ? $(a).text() : "";
          var noFollow = $(a).attr("rel");
          var isDoFollow =  ! (noFollow && noFollow === "nofollow");
  
          var linkUri = URI.linkToURI(parentUrl, link);
  
          pm.crawlLink(parentUrl, linkUri, anchor, isDoFollow, function(){
            addLinkToQueue(result, parentUrl, linkUri, anchor, isDoFollow, callback);
          });
  
        }
        else {
          callback();
        }
  
  }
docs: Extract info of ahref & send the info to the plugins
  
  
  @param The HTML body containing the link (Cheerio wraper)
  @param The http response with the crawl options
  @param The anchor tag
  @param callback()