CKEDITOR 4 Paypal Insert Plugin plugin.js

/* This is my plugin.js code */
(function()
{

    CKEDITOR.plugins.add( 'paypal',
    {
        requires: 'dialog',
        lang: ['en'],
        init: function( editor )
        {
            CKEDITOR.dialog.add( 'paypalChooseButton', CKEDITOR.getUrl( this.path + 'dialog/paypal.js' ) );
            CKEDITOR.dialog.add( 'paypalCreateSingleButton', CKEDITOR.getUrl( this.path + 'dialog/paypalSingleButton.js' ) );
            CKEDITOR.dialog.add( 'paypalCreateMultiButton', CKEDITOR.getUrl( this.path + 'dialog/paypalMultiButton.js' ) );

            editor.addCommand( 'paypalChooseButton',
            {
                exec: function( editor )
                {
                    editor.openDialog( 'paypalChooseButton' );
                    return;
                }
            });

            editor.ui.addButton( 'paypal',
            {
                label: 'Insert PayPal Button',
                command:'paypalChooseButton',
                icon: this.path + 'img/paypal.png'
            });

        }
    });

})();