Preview resolved config

[bentsherman]

It would be useful to preview the resolved config for a process, similar to the CSS viewer in a web browser's developer view.

Likely the best place to do this would be on the process invocation using the CodeLens request: https://code.visualstudio.com/blogs/2017/02/12/code-lens-roundup

CodeLens is pretty open-ended, you just attach a link to an AST element and when the user clicks the link, you can essentially do whatever you want. So we could render a cascading view of settings applied from various configs as well as the resolved config.