Users can't edit wiki

[CendioOssman]

Describe the bug
Only maintainers can currently edit our wiki, making it almost useless as the point of the wiki is to have documentation that the community can maintain.

Additional context
The reason the wiki is locked down is because there is too much malware being added to GitHub wikis. And GitHub provides absolutely no tools to deal with the issue.

In other words, getting GitHub doesn't seem feasible. We need to look at alternatives.

This could be an option where we can still host things on GitHub:

https://github.com/Drassil/git-wiki-theme