jQuery.fn.rkgallery = function(options){
    options = jQuery.extend({
        fadetime: '1000',
        switchtime: '10000'
    }, options);

    var fadetime = options.fadetime
    var switchtime = options.switchtime

    function changeImage () {
        jQuery('#header-image').children(':nth-child(2)').fadeIn(fadetime, function(){
            jQuery('#header-image').children(':first-child').hide();
            jQuery('#header-image').append( jQuery('#header-image').children(':first-child') );
        });
    }

    if (jQuery('#header-image').length != 0) {
        jQuery('#header-image').children().hide();
        jQuery('#header-image').children(':first-child').show();
        window.setInterval( changeImage, switchtime );
    }

}