<!--- Verify first that your feature was not already discussed on GitHub -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Describe the new feature/improvement briefly below -->
Add new commands to the Redfish remote_management modules to perform firmware update requests.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
redfish_config.py
redfish_utils.py

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
Operators need a way to update firmware on Redfish managed systems. Would like an extension made to be able to perform SimpleUpdate actions with a specified firmware image. At the very minimum we can point to a remote HTTP/TFTP/SCP/etc server, but if possible, it might be good to spin up a lightweight HTTP server to service the request in case one isn't provisioned.

<!--- Paste example playbooks or commands between quotes below -->
```yaml
  - name: Pull style update
    redfish_config:
      category: Update
      command: PullUpdate
      image: http://my.file.repo/someimage.bin
      targets:
        - /redfish/v1/Systems/1
        - /redfish/v1/Systems/2
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
```

<!--- HINT: You can also paste gist.github.com links for larger files -->

"""
        Get Redfish ExtendedInfo message from response payload if present
        :param error: an HTTPError exception
        :type error: HTTPError
        :return: the ExtendedInfo message if present, else standard HTTP error
        """
        msg = http_client.responses.get(error.code, '')
        if error.code >= 400:
            try:
                body = error.read().decode('utf-8')
                data = json.loads(body)
                ext_info = data['error']['@Message.ExtendedInfo']
                msg = ext_info[0]['Message']
            except Exception:
                pass
        return msg
    def _init_session(self):