Contribution docs

[askvortsov1]

We should expand our docs on contributing to Flarum, especially non-code ways to contribute to Flarum (e.g. how to contribute to docs. We should also create more resources helping people who are new to Flarum contribute.

We need to decide on a location for these docs. The way I see it, there are 3 options:

1. Under the current "contributing" page
2. In a new category in the "Guide" section
3. In the "Internal" section (in which case, we might want to rename that to "Contribute", and cover both internal and external contributions)

I think I currently prefer (2), but would love to hear everyone's thoughts.

[davwheat]

I like the idea of 2 as well, preferably towards the top to give it more prominence?

[SychO9]

2 would do just fine

[luceos]

2 means to increase the importance of that page and make it a category? If so that's my choice too.