Make s3 backup keys optional

[podulator]

When running in aws, roles are the preferred way of accessing resources, rather than keys. http://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html Could you make AWS Access and Secret keys optional for the s3 backup, so roles can be used in an aws environment? Thanks, Mat

[dashrb]

I too use ec2 instance profiles, and I have patched my own system to support this. Pull request incoming! For clarity, I suggest modifying the title of this issue to "Make S3 Access Keys optional (for backups to S3)", as there are "backup encryption keys" which are not relevant to what you want here.