Feedback from Jan 24 meeting:

- Use camel case for variable names.
- Use list syntax. Mark list members as strings.
- Be more explicit about "strictly conform to".
- Remove canonical config.
- Replace removeChild().
- "set and filter" take a "safe" boolean
- Use "set difference" instead of intersection complement.
- Introduce "dataAttributes" for data-* attributes.
- Add special cases for javascript:-URLs and templates ("funky elements") back in
- Minor edits.