Add OpenStack Swift support
Add OpenStack Swift support

Refactor all S3 code to use the django storage API and add swift
settings for openstack deployments

naresh21/synergetics-edx-platform,naresh21/synergetics-edx-platform,synergeticsedx/deployment-wipro,synergeticsedx/deployment-wipro,naresh21/synergetics-edx-platform,naresh21/synergetics-edx-platform,synergeticsedx/deployment-wipro,synergeticsedx/deployment-wipro