[Feature Request] el-upload 自定义上传的实现http-request覆盖默认的上传行为，批量上传时能否将批量上传的列表传入？以便知道是否处理完毕

### Existing Component
是

### Component Name
el-upload

### Description

export default {
methods: {
//now
upload(file) {
console.log(file);
},
//hope
upload(file, fileList) {
console.log(file, fileList);
}
}
}