Create adblock-rust Wiki for users

Brave Shields, specifically, the `adblock-rust` product is one of the primary reasons users choose Brave. It is important that users understand what operators are supported by Brave's adblock and what operators are not supported. Going into the [adblock-resources](https://github.com/brave/adblock-resources) repo is not something that most users will do and even doing so doesn't answer all questions (especially about more advanced features like scriptlets).

As a guide, Raymond Hill has written an excellent [wiki for uBO](https://github.com/gorhill/uBlock/wiki). Please take inspiration from this gorhill and support your users by creating a wiki for this product.