handle FileList objects

Recurse FileList objects from file inputs with multiple files and add all the files, this will generate an array on the server when getting the fileattribute key.

I use this in Flask (python) as an example:
files = request.files.getlist('files')

Which returns when using fileAtrribute: 'files':
[<FileStorage: u'file1.png' ('image/png')>, <FileStorage: u'file2.png' ('image/png')>]