Automate Conversion of US/UC/UCC from MD to HTML

[mmccool]

• Issues for use cases, use case categories, and user stories appear as structured MD
• It would be nice to have a script to convert these to HTML for inclusion in the document
• We had an earlier tool, written in Perl, to convert from MD to HTML, but that was for the old template: https://github.com/w3c/wot-usecases/blob/main/CONTRIBUTIONS/md2html.pl
• If we had something that could parse MD and turn it into JSON, then we could do what we want
• This exists: https://github.com/njvack/markdown-to-json to parse github MD into JSON...
• Then once we have JSON, we can extract the bits we want and output HTML using a template library like moustache

[chachamimm]

I have verified that md2html.pl works. There was one problem, but i confirmed that it could convert from MD to HTML. There is the following description in the Issue made in YAML, which I don't think it is necessary when converting from MD to HTML.

```markdown

```

So I created new PR #329.