code: function (name, factory, cfg) {
              ComboLoader.add(name, factory, cfg, arguments.length);
          }
docs: Registers a module with the KISSY global.
  @param {String} name module name.
  it must be set if combine is true in {@link KISSY#config}
  @param {Function} factory module definition function that is used to return
  exports of this module
  @param {KISSY} factory.S KISSY global instance
  @param {Object} [cfg] module optional config data
  @param {String[]} cfg.requires this module's required module name list
  @member KISSY
  
  
  // dom module's definition
  KISSY.add('dom', function(S, xx){
  return {css: function(el, name, val){}};
  },{
  requires:['xx']
  });