code: function( name, type, definition )
  	{
  		this._.items[ name ] =
  		{
  			type : type,
  			// The name of {@link CKEDITOR.command} which associate with this UI.
  			command : definition.command || null,
  			args : Array.prototype.slice.call( arguments, 2 )
  		};
  	}
docs: Adds a UI item to the items collection. These items can be later used in
  the interface.
  @param {String} name The UI item name.
  @param {Object} type The item type.
  @param {Object} definition The item definition. The properties of this
  object depend on the item type.
  @example
  // Add a new button named "MyBold".
  editorInstance.ui.add( 'MyBold', CKEDITOR.UI_BUTTON,
  {
  label : 'My Bold',
  command : 'bold'
  });