**polyfill for curl_file_create**

```
if (!function_exists('curl_file_create')) {
    function curl_file_create($filename, $mimetype = '', $postname = '') {
        return "@$filename;filename="
            . ($postname ?: basename($filename))
            . ($mimetype ? ";type=$mimetype" : '');
    }
}
```

http://php.net/manual/ru/function.curl-file-create.php#114538