Automate docs with eslint-doc-generator

[bmish]

eslint-doc-generator is a CLI tool I built for automating the generation of the README rules list table and rule doc title/notices for ESLint plugins. It follows common documentation conventions from this and other top ESLint plugins and will help us standardize documentation across ESLint plugins (and generally improve the usability of custom rules through better documentation and streamline the process of adding new rules). It has 100% test coverage and is used in many of the top ESLint plugins already.