code: function create(item, model, data) {
      var serverProps = serverProperties(item, model, data).properties;
      return utils.socketPut(model.io, model.url + '/create/', serverProps).then(function(response) {
          _.merge(serverProps, response);
          return update(item, model, serverProps);
      }).then(function() {
          // Refresh all items that were referenced - some of their properties might change
          return Promise.all(_.map(serverProps.refresh, function(item) {
              return item.refresh();
          }));
      });
  }
docs: Creates the item on the server
  
  @param {object} item
  @param {Model} model
  @param {object?} data
  @returns {Promise}