Allow role ARN to be passed instead of profile name
Allow the role ARN to be specified instead of the configuration profile name. This will allow the tool to be used in situations where the .aws/config is not setup, and it's just simpler to specify the ARN for simple or automated usage. If a role ARN is provided, but requires MFA, the -M flag has been added so you can provide the MFA device ARN directly as well, instead of relying on the value from the .aws/config file.
Example
MFA not required:
aws-runas arn:aws:iam::123456789012:role/123456789012-Administrator -- aws s3 ls
MFA required:
aws-runas -M arn:aws:iam::987654321098:mfa/iam_user arn:aws:iam::123456789012:role/123456789012-Administrator -- aws s3 ls
Don't worry, the previous behavior of using a "friendly" profile name still works, this just provides another option for running the command.