Added missing season type 'alttwo'

[Kianda]

There are currently 7 types but here on jellyfin-plugin-tvdb only 6 are supported.
I've just added the one missing ^^

FYI: Here is the payload from thetvdb.com API v4 (seasons/types)

Swagger:
https://thetvdb.github.io/v4-api/

{
  "status": "success",
  "data": [
    {
      "id": 1,
      "name": "Aired Order",
      "type": "official",
      "alternateName": null
    },
    {
      "id": 2,
      "name": "DVD Order",
      "type": "dvd",
      "alternateName": null
    },
    {
      "id": 3,
      "name": "Absolute Order",
      "type": "absolute",
      "alternateName": null
    },
    {
      "id": 4,
      "name": "Alternate Order",
      "type": "alternate",
      "alternateName": null
    },
    {
      "id": 5,
      "name": "Regional Order",
      "type": "regional",
      "alternateName": null
    },
    {
      "id": 6,
      "name": "Alternate DVD Order",
      "type": "altdvd",
      "alternateName": null
    },
    {
      "id": 7,
      "name": "Alternate Order 2",
      "type": "alttwo",
      "alternateName": null
    }
  ]
}

[scampower3]

Probably needs additional modifications to jellyfin-web like jellyfin/jellyfin-web#5505

[Kianda]

Yes true, it needs additional modifications to jellyfin-web but it's not mandatory.
The current downside is that you must provide the 'alttwo' order inside the tvshow.nfo cause it's not available from the GUI.

Example of tvshow.nfo

<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <tvshow> <displayorder>alttwo</displayorder> </tvshow>

jellyfin-plugin-tvdb will read this without any issues!

More info: https://jellyfin.org/docs/general/server/metadata/nfo/#naming-nfo-files