Create role does not allow for document policies to be passed to it
Adding put_role_policy, get_role_policy, and list_role_policies, update_assume_role_policy
Removing duplicate import
Merge branch 'enhancedIamRoleSupport' of https://github.com/kevgliss/moto into kevgliss-enhancedIamRoleSupport
Updates for IAM changes.
Merge branch 'kevgliss-enhancedIamRoleSupport'