Correct output for authorize-security-group-ingress

Verified that we just a return value of {"return": "true"}.
This also syncs up with the API docs:
http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-AuthorizeSecurityGroupIngress.html#ApiReference-query-AuthorizeSecurityGroupIngress-Response
Merge branch 'doc-examples-ec2' into develop

* doc-examples-ec2:
  Correct output for authorize-security-group-ingress