Add Xbox documentation

[hunterjm]

Proposed change

Add documentation for the Xbox Integration.

Type of change

• Spelling, grammar or other readability improvements (current branch).
• Adjusted missing or incorrect information in the current documentation (current branch).
• Added documentation for a new integration I'm adding to Home Assistant (next branch).
  • I've opened up a PR to add logo's and icons in Brands repository.
• Added documentation for a new feature I'm adding to Home Assistant (next branch).
• Removed stale or deprecated documentation.

Additional information

• Link to parent pull request in the codebase: Add Xbox Integration core#41697
• Link to parent pull request in the Brands repository: Add Xbox brands brands#1928
• This PR fixes or closes issue: N/A

Checklist

• This PR uses the correct branch, based on one of the following:
  • I made a change to the existing documentation and used the current branch.
  • I made a change that is related to an upcoming version of Home Assistant and used the next branch.
• The documentation follows the Home Assistant documentation standards.

[MartinHjelmare]

Should we mention what consoles are supported? It looks like it's only Xbox One and later?

[hunterjm]

Ok, I'm done adding changes for 0.117 :)

[SeanPM5]

For the media source section, it might be worth including a brief mention about potential delays in newly downloaded content appearing in the Media Browser.

When I downloaded a few extra media player apps on my console to test this integration, it took ~21 hours for them to appear in HA. Not sure if that's a consistent behavior though...

[hunterjm]

LGTM

[frenck]

Thanks, @hunterjm 👍

Awesome work 🎉