Feature Request: Support AWS IAM Authentication

[matiasgarciamarset]

This library https://github.com/aws/aws-msk-iam-auth enables developers to use AWS Identity and Access Management (IAM) to connect to their Amazon Managed Streaming for Apache Kafka (Amazon MSK).

Problem
Cruise-control does not support AWS IAM Authentication by default, returning this error "org.apache.kafka.common.config.ConfigException: Invalid value software.amazon.msk.auth.iam.IAMClientCallbackHandler for configuration sasl.client.callback.handler.class: Class software.amazon.msk.auth.iam.IAMClientCallbackHandler could not be found.", forcing developers to re-compile the current code to include it.

Solution
Adding the aws library (https://github.com/aws/aws-msk-iam-auth) in the gradle imports should be enough

implementation "software.amazon.msk:aws-msk-iam-auth:2.0.2"