Support wavedrom format for waveforms

[mithro]

wavedrom.io is a great format for documenting waveforms and their various features that has multiple compatible renderers out there (undulate (https://github.com/LudwigCRON/undulate) is a Python library which supports rendering the format.). See also https://wavedrom.com/tutorial.html

The format is documented at https://github.com/wavedrom/wavedrom/wiki/WaveJSON

Wavedrom is particularly powerful when combined with something like Sphinx for documentation generation. You can seem some examples at https://ci.betrusted.io/betrusted-soc/doc/engine.html#detailed-timing-operation