basic tests structure
Ella 3 Box has an attribute 'name' instead of 'opts'
tests with full coverage of models, urls and views, minor bug fixes
test raising of Http404 in download_attachment view
added CachedForeignKey for photo and type of attachment
removed filter_horizontal for publishables, becouse of inefficient for a lot of objects
Standard python packaging
name fix
sanoma version merged with ella version
fixed PEP8
used name first in filename property
updated setup.py and requirements etc.
added README file
Merge pull request #1 from SanomaCZ/master

merged original ella-attachments with sanoma ella-attachments