Tautulli

* No additional changes from v2.1.20-beta.

* Monitoring:
* Fix: Fetch messing season info when "Hide Seasons" is enabled for a show.
* Fix: Video and Audio details sometimes missing on activity cards.
* Notifications:
* New: Added UTC timestamp to notification parameters. (Thanks samwiseg00)
* New: Added TAUTULLI_PUBLIC_URL to script environment variables. (Thanks samwiseg00)
* UI:
* Change: Automatically redirect '/' to HTTP root if enabled.
* API:
* New: Added return_hash parameter to pms_image_proxy command.
* New: Added session_id parameter to get_activity command.
* Other:
* Change: Linux systemd startup script to use the "tautulli" group permission. (Thanks samwiseg00)

* Notifications:
* New: Added Webhook notification agent.
* Fix: Scripts failing due to unicode characters in substituted script arguments.
* Change: Ability to override PYTHONPATH for scripts.
* Remove: Notify My Android notification agent.
* Newsletters:
* New: Added option for threaded newsletter emails.
* Fix: Missing space in newsletter format.
* UI:
* New: Added Windows system tray icon.
* Fix: Plex OAuth not working with Plex remote access disabled. (Thanks samwiseg00)
* API:
* Fix: SQL command creating a database backup every time. (Thanks samwiseg00)

* Monitoring:
* Fix: Progress bar on activity cards showing incorrect 100% when starting a stream.
* Notifications:
* Fix: Notification text boxes scrolling to top when inputting text.
* Change: Skip formatting invalid notification parameters instead of returning default text.
* UI:
* Fix: Padding around search bar causing the navigation bar to break on smaller screens.

* Notifications:
* Change: Use default selected stream for media info in notifications.
* UI:
* New: Automatically discover localhost Plex servers in server selection dropdown.
* Change: Save Datatables state indefinitely.

* Monitoring:
* Fix: Plex server not detected as down during sudden network loss.
* Notifications:
* Fix: Incorrect rounding of percentages in some cases.
* Fix: Incorrect stream duration value for playback start notifications.
* New: Added critic rating parameter for Rotten Tomatoes ratings.
* Newsletters:
* Fix: Typo in "seasons" when there is only one additional season.
* UI:
* New: Added ability to use Plex OAuth to login to Tautulli.
* API:
* Fix: Unicode characters causing get_logs command to return bad data.
* New: Added rating_image and audience_rating_image to get_activity and get_metadata commands.