code: function init() {
          var items = doc.getElementsByTagName("script");
  
          // look for a script with a data-head-init attribute
          for (var i = 0, l = items.length; i < l; i++) {
              var dataMain = items[i].getAttribute("data-headjs-load");
              if (!!dataMain) {
                  api.load(dataMain);
                  return;
              }
          }
      }
docs: /* Parts inspired from: https://github.com/jrburke/requirejs
  **********************************************************