Update Norwegian contribution guidelines

[Vages]

In reaction to #417

[aplaice]

Makes sense — you have a better idea of how good or bad Norwegian Wikipedia is, and what other Norwegian sources are reputable.

We'll likely be switching to using English Wikipedia as authoritative for factual information, for all languages, while still using the respective language sources for spelling and alternative names. For instance, if English Wikipedia claims that New-Town is the capital of Examplestan, while SNL claims that it's Gammelstad but states that the Norwegian name for New-Town is Nystad, sometimes also known as Alternativstad, then in the Norwegian deck, we'll have Nystad as the capital of Examplestan, mention Alternativstad as an alternative name in the Capital info and probably, (if the change from Old-Town to New-Town was recent) mention Gammelstad as a previous capital.

(Apologies if I've butchered Norwegian in my made-up names...)

The idea is that the actual identity of the capital (or the best guess of what it is) doesn't depend on language — just the name(s) do.

Hopefully you don't have any objections, but if you do, please say so, and we'll try to find a solution.