function show(gallery, group, index){

    //console.log("show", gallery, config);

    anchors = gallery;

    if(group){

        options_group = group;
        options_onshow = group["onshow"];
        options_onchange = group["onchange"];
        options_onclose = group["onclose"];
        index = index || group["index"];
    }

    init_gallery(index);
}
@param {!HTMLCollection|Array} gallery
@param {Object=} group
@param {number=} index