daux.io/docs/05_Config/15_Fields/File.md

Creates a single file upload field.

"file": {
    "title": "File Field",
    "type": "file"
}

Returns an array.

[file] => Array
    (
        [caption] =>
        [date] => 11/1/2012
        [url] => http://todaycms.s3.amazonaws.com/...filename.pdf
        [name] => filename.pdf
    )