sends files from uploader body to server
| id | number| string| function | file ID or callback function | 
$$("upl1").send(function(response){
    if(response)
        webix.message(response.status);
});
//response contains serverside response
The method allows sending all the pre-added files at a time as well one file specified by ID::
$$("upl1").send();
$$("upl1").send(id);
Additionally, extra data can be defined in the uploader configuration through the formData property:
webix.ui({ 
    view:"uploader",
    formData:{
        param1:value1,
        param2:value2
    },
    ...
});