Issue with MPO type of JPEG file

[jbaack]

Pillow detects some JPEGs as format MPO. These can be treated as JPEGs in all other way - but got an error when Da Vinci tries to determine the file extension.

Adding the final line below in formats.py fixed my simple use (from django-thumbnails).

EXTENSIONS = {
'JPEG': 'jpg',
'GIF': 'gif',
'PNG': 'png',
'PDF': 'pdf',
'TIFF': 'tif',
'BMP': 'bmp',
'WEBP': 'webp',
'MPO': 'jpg'
}