Similar to the video field, with default file extension validation. Should use the filepond editor by default. This will require code in the core plugin to create the field type and template, like https://github.com/WPUserManager/wp-user-manager/commit/283afa5e975e9ba4c1f80f608a68125a3156707c ## Related - [#42](https://github.com/WPUserManager/wpum-custom-fields/issues/42)
