Improve rule development experience

[kmonihen]

This is very broad and will likely generate new issues as we flesh it out. We need to improve the tools and documentation around config-lint rule development.

Initial work:

• Look at replicating the built-in rule testing so that testing can be done on an external structure of rules/test files.
• Create a tool to generate initial rule structure to bootstrap rule development.
• Better documentation around rule development workflow.