Implement Admin APIs for Roles

[mikelax]

Feature Overview

Is your feature request related to a problem? Please describe.
As an admin usher user, I would like to have APIs available to manage Roles. Some of the APIs are already implemented, this issue should complete the missing APIs.

API Design

Status	URL	Auth	Params	Notes
TODO	PATCH /roles/:role_key	bearerAdminAuth	name and/or description: body	Update Role attributes
TODO	DELETE /roles/:role_key	bearerAdminAuth	role key: path, required	Delete a Role

Implementation Notes

• The source files should be placed in the src/api_endpoints/roles folder.
• Move the existing endpoint_roles.js file from the api_endpoints folder to api_endpoints/roles and also rename the file. This will also require updating the open api spec x-swagger-router-controller.
• Refactor the createRole function to handle and return errors like all newer APIs.

Questions