Support wavedrom markdown in Veryl

[saturn77]

The Rust library mdbook-wavedrom allows for inserting wavedrom descriptions into document.

This is a feature request to support this crate with Veryl.

https://github.com/JasMoH/mdbook-wavedrom

So for example, inside of some comments within a module:

/*

{signal: [
  {name: 'clk', wave: 'p.....|...'},
  {name: 'dat', wave: 'x.345x|=.x', data: ['head', 'body', 'tail', 'data']},
  {name: 'req', wave: '0.1..0|1.0'},
  {},
  {name: 'ack', wave: '1.....|01.'}
]}

*/

Would have this image inserted into the html, upon running Veryl doc

[dalance]

I've implemented wavedrom integration.
It's very good feature!