[Feature] Session MMR Tracking

[GrantJL]

Add an optional Session MMR Tracking

• Tracks current playlist (shows current playlist, tracks multiple throughout session)
• Tracking Display options (toggle and orderable)
  • Current Playlist and MMR
  • # Game
  • # Wins, Losses, Win/Loss, Win/Games, Win %
  • # Win/Loss Streak
  • # MRR Change Last Match / Session
  • More...?
  • Current User Time?
• Optionally Attach Stats to bottom of scoreboard (or own custom position, anchors)