Add community guides to docs

[mikeybinns]

I've had this idea for a community guides section in the docs. These would be written by community members, and marked as such on the site so people don't blame Remix staff if they don't work for them, but it might be a good way to cover lots of use cases without taking up Remix team time, or diluting the docs with many packages.

I thought of this as I have seen many questions in the discord help channel similar to "How do I integrate X into Remix".

As a bit of a cover for outdated content, you could require when a guide is added, they add some meta data like:

• "Submitted by:" The community member who submitted the guide
• "Tags:" Relevant tags for categorisation.
• "Tested up to:" which would be the most Remix and required dependencies version that the guide has been tested with
• "Requires:" The least recent version of Remix and required dependencies the guide is tested with

And using that data, you could flag the guides if the guide is possibly outdated and effectively display a large number of guides
(tags on the left sidenav, guides with the tag on the right sidenav).

I think to set this up, the team would just need to provide a writing guide for consistency (with sections like "how to implement code blocks in Remix docs")