Enforcing type safety in Dottydoc code examples

This project aims to extend the Dotty documentation compiler (alias "Dottydoc") to make code examples found in comments type safe, with the purpose of ensuring that documentation does not become out of date. This will be done by compiling and running each example as the documentation is being generated, alerting the user if errors are found. Each line of the code examples on the generated documentation page will then be annotated with the output of its expression, in the same style as the scala REPL.