New look and feel for IRIS documentation

For IRIS 2019.1 and later, the documentation has a new look and feel. Check it out:

https://docs.intersystems.com/irislatest/csp/docbook/Doc.View.cls
 

The underlying changes include a new style sheet and a complete rewrite of the code we use to generate HTML.  (There is now an underlying API for retrieving content as JSON, as well as a large set of unit tests -- for those of you who like that kind of thing!)

We're adopting the same HTML generation code for various static HTML files also served up on docs.intersystems.com, including the Supported Platforms document, the PDF index document, and (soon) the website landing pages.

The goal is to have less code and more tests. Let us know what you think!