Update descriptions of -vanilla

[GeckoEidechse]

Required once

• Rework -vanilla to be a vanilla compatibility mode NorthstarLauncher#601

is merged.

[GeckoEidechse]

cc @ASpoonPlaysGames (PR author) and @itscynxx (wiki PR goat <3)

[ASpoonPlaysGames]

NorthstarWiki/docs/installing-northstar/troubleshooting.md

Line 131 in 32e2a2a

Adding `-vanilla` or removing the `-northstar` will start the normal game when you have Northstar installed

NorthstarWiki/docs/using-northstar/launch-arguments.md

Line 8 in 32e2a2a

| `-vanilla` | Disables Northstar loading | |

NorthstarWiki/docs/installing-northstar/troubleshooting.md

Line 134 in 32e2a2a

* `Your library > Right click TF|2 > Properties > General > Launch Options > -northstar or -vanilla`

These are the only mentions of -vanilla

[itscynxx]

Currently heading towards Thanksgiving dinner; if spoon doesn't want to do it, I'll do it in 6-8 hours maybe

Also, thanks for finding the current mentions of -vanilla spoon

would write a better comment but github mobile