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##### SUMMARY
<!--- Describe the new feature/improvement briefly below -->
During the 2019 APTS Plugfest, it was noted that the `GetFirmwareInventory` command was gathering the `FirmwareInventory` from the `UpdateService`, but not the `SoftwareInventory`.

There are two options to address this request:

1. Update the `GetFirmwareInventory` command to also gather the `SoftwareInventory`.
2. Add a new `GetSoftwareInventory` command.

I'll get input on these two options. [Per Tools Task Force call, agreed on option 2.]

##### 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_facts.py
redfish_utils.py

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
Operators want to be able to get `SoftwareInventory` as well as `FirmwareInventory`. There is currently no way the gather the `SoftwareInventory` using the Ansible Redfish modules.

<!--- Paste example playbooks or commands between quotes below -->
**Option 1:**
```yaml
  tasks:

  - name: Get Firmware and Software Inventory
    redfish_facts:
      category: Update
      command: GetFirmwareInventory
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result
```

**Option 2:**
```yaml
  tasks:

  - name: Get Firmware Inventory
    redfish_facts:
      category: Update
      command: GetFirmwareInventory
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result

  - name: Get Software Inventory
    redfish_facts:
      category: Update
      command: GetSoftwareInventory
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result
```


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

result['ret'] = True
            data = response['data']
            if data[u'Members']:
                for controller in data[u'Members']:
                    controller_list.append(controller[u'@odata.id'])
                for c in controller_list:
                    uri = self.root_uri + c
                    response = self.get_request(uri)
                    if response['ret'] is False:
                        return response
                    data = response['data']
                    controller_name = 'Controller 1'
                    if 'StorageControllers' in data:
                        sc = data['StorageControllers']
                        if sc:
                            if 'Name' in sc[0]:
                                controller_name = sc[0]['Name']
                            else:
                                sc_id = sc[0].get('Id', '1')
                                controller_name = 'Controller %s' % sc_id
                    drive_results = []
                    if 'Drives' in data:
                        for device in data[u'Drives']:
                            disk_uri = self.root_uri + device[u'@odata.id']
                            response = self.get_request(disk_uri)
                            data = response['data']
                            drive_result = {}
                            for property in properties:
                                if property in data:
                                    if data[property] is not None: