[Architecture] Updated, simplified PCP API

I've updated my pull request at https://github.com/GPII/universal/pull/549 to incorporate a further simplified version of the PCP API, which is more closely focused on the needs of the UI. This now encodes the model state corresponding to the settings widgets directly rather than this

Re: [Architecture] Alternatives to the "marked" markdown renderer...

Hi, All. I have created pulls against gpii-handlebars and infusion-docs to migrate to markdown-it. Thus far my experience with markdown-it has been pretty positive, it was basically a