support for AWS s3 backups

in chron job, call with
echo "secret_key=$AWS_SECRET_ACCESS_KEY">> s3cmd.ini; echo "access_key=$AWS_ACCESS_KEY_ID" >> s3cmd.ini; s3cmd --recursive cp s3://impactstory-uploads-production/active s3://impactstory-uploads-production/backup --config=s3cmd.ini
Merge branch 'share-products' of github.com:total-impact/total-impact-webapp into share-products