Resolve correct path for attachment from settings.MEDIA_ROOT, fix infinite recusion on delivery failure.
Resolve correct path for attachment from settings.MEDIA_ROOT, fix infinite recusion on delivery failure.

Goury/django-mail-queue,dstegelman/django-mail-queue,styrmis/django-mail-queue,Goury/django-mail-queue,dstegelman/django-mail-queue,winfieldco/django-mail-queue