serve media files through app

contracts/migrations/0009_alter_contractfile_file.py

contracts/models.py

media_server/__init__.py

media_server/admin.py

media_server/apps.py

media_server/migrations/__init__.py

media_server/models.py

media_server/tests.py

media_server/urls.py

media_server/views.py

nginx.conf

registry/settings/base.py

registry/urls.py