Create a new account automatically when role is created, and delete when role deleted

It would be useful for new QA accounts to be automatically created when user roles are added. On deploys, it would save from having to run the drush command or uninstall/reinstall the module after deploy.

Automatic deletion of QA accounts when the corresponding roles are deleted would be a useful feature as well.

There probably should be configuration involved so that automatic account creation and deletion are opt in.