Added Midnight portals

[Oylex]

I added the new portals from Midnight.

I kept the new "current_season" category commented out until it starts

One thing I was not 100% sure, is that there is a new portal for Skyreach, so I added it next to the old one.

If learning one automatically makes you learn the other one, then we can remove one of them.

If they stay separate portals, we could clean this up by showing only one of them and priorizing the learned one.

["skyreach"] = {spellID = 159898, nameKey = "DUNGEON_SKYREACH"},
["skyreach_midnight"] = {spellID = 1254557, nameKey = "DUNGEON_SKYREACH"}, -- Skyreach (Midnight)

I also added the translations based on Wowhead and the Blizzard's website, most locales keep the expansion names the same.

I also increased the height of the option frame to fit the new expansions (adding a scroll bar seemed a bit complicated to me, I'm not used to coding for WoW )

Let me know if there is something I should fix here, I already use this change in my WoW and it seems to work fine (along with the other PR #13)

[Zazou89]

Hi ! I’m sorry. I’m very busy at the moment, but I’ll take a look as soon as possible! Thank you very much.