Support the use of permission boundaries when creating IAM roles

[ckamps]

As a technologist working in a development AWS account that has guardrails implemented via an IAM permissions boundary, I need the CloudFormation templates to provide me with the option to specify the ARN of an IAM permissions boundary policy so that the permissions boundary can be supplied during creation of IAM roles in these templates.

Background

This particular AWS account and development environment provides technologists with freedom to create and manage IAM roles, but that work is subject to the technologist being required to associate an existing IAM permissions boundary during role creation. That permission boundary inhibits technologists from modifying the underlying foundation of their development environment.