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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 -->

msg: "{{ result.redfish_facts.virtual_media.entries | to_nice_json }}"
  - name: Get Volume Inventory
    redfish_info:
      category: Systems
      command: GetVolumeInventory
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result
  - debug:
      msg: "{{ result.redfish_facts.volume.entries | to_nice_json }}"
  - name: Get Session information
    redfish_info:
      category: Sessions
      command: GetSessions
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result
  - debug:
      msg: "{{ result.redfish_facts.session.entries | to_nice_json }}"
  - name: Get default inventory information
    redfish_info:
      baseuri: "{{ baseuri }}"
      username: "{{ username }}"
      password: "{{ password }}"
    register: result
  - debug:
      msg: "{{ result.redfish_facts | to_nice_json }}"
  - name: Get several inventories